simplify the output so its readable, parseable, easy to write - ics2txt - convert icalendar .ics file to plain text
HTML git clone git://bitreich.org/ics2txt git://enlrupgkhuxnvlhsf6lc3fziv5h2hhfrinws65d7roiv6bfj7d652fid.onion/ics2txt
DIR Log
DIR Files
DIR Refs
DIR Tags
DIR README
---
DIR commit 7ef52e239bfc8757d45f3d868920dba32dcb5b61
DIR parent 31dd5e1db68625ddd31ab25ce43877ca77df927f
HTML Author: Josuah Demangeon <mail@josuah.net>
Date: Sun, 7 Jul 2019 21:50:43 +0200
simplify the output so its readable, parseable, easy to write
Diffstat:
M Makefile | 4 ++--
M README | 109 ++++++++++++++++++++-----------
D doc/rfc5545.txt | 9411 -------------------------------
M ics2txt | 183 ++++++++++++++-----------------
M ics2txt.1 | 44 +++----------------------------
D txt2ics | 93 -------------------------------
D txt2ics.1 | 51 -------------------------------
7 files changed, 156 insertions(+), 9739 deletions(-)
---
DIR diff --git a/Makefile b/Makefile
@@ -1,5 +1,5 @@
-BIN = ics2txt txt2ics
-MAN1 = ics2txt.1 txt2ics.1
+BIN = ics2txt
+MAN1 = ics2txt.1
all:
DIR diff --git a/README b/README
@@ -1,52 +1,83 @@
-agenda
-================================================================================
+ics2txt
+=======
-*agenda* is an awk scripts to deal with iCal [1] format to publish,
+*ics2txt* is an awk scripts to deal with iCal [1] format to publish,
display and convert *.ics files.
-It is still a work in progress and should be released soon. In the meantime,
-example output from l'agenda du libre [2]:
+[1]: https://tools.ietf.org/rfc/rfc5545.txt
- [2017/04]
+Sample output:
- 19 16:00 Linux et les Logiciels Libres
- 19:00 château Goerg, Callian, Provence-Alpes-Côte d'Azur, France
- Venez découvrir Linux et les logiciels libres, mais aussi vous
- faire aider avec votre matériel informatique quel qu’il soit,
- imprimante, box, tablette, smartphone y compris.
+2019-02-02
- 16:30 Permanence GNU/Linux - Les Quatre Libertés
- 18:30 10 rue François Henry d’Harcourt, Montpellier, Occitanie, France
+07:30 Welcome to FOSDEM 2019
+07:55 Janson
+ FOSDEM welcome and opening talk.
- 17:00 Atelier artiste - hacker
- 19:00 62 rue Fiéffé, Bordeaux, Nouvelle-Aquitaine, France
- Ateliers-cours à la fabrique-pola - L@bx
+08:30 The State of Go
+09:00 UD2.120 (Chavanne)
+ Go 1.12 is planned to be released in February 2019 and this talk
+ covers what's coming up with it.We'll talk about Go Modules, the
+ proposals for Go 2, and all of the new things you might have missed.
- 17:00 Introduction à la programmation de jeux
- 19:00 55 rue de Vincennes, Montreuil, Île-de-France, France
+09:30 HTTP/3
+10:30 UD2.208 (Decroly)
+ HTTP/3 is the next coming HTTP version. This time TCP is replaced by
+ the new transport protocol QUIC and things are different yet again!
- 17:30 SGEG
- 20:00 8 rue Colary, Carnac, Bretagne, France
- Le SGEG (Sansten GNU Easy Group) vous invite tous les
- 3e mercredi de chaque mois au SGEG Meeting pour discuter de
- Logiciel Libre, boire un verre, manger un morceau et surtout se
- rencontrer !
+10:05 Minimalism matters
+10:25 K.4.201
+ Minimalism matters in computing. To trust systems we need to be able
+ to understand them completely. Openssl heartbleed disaster was caused
+ by code no longer being minimalistic, even if it is free and open
+ source software. Hardware manfucturers and proprietary closed source
+ solutions make things even worse with expectations of intrusion to
+ privacy and backdoors if we don't aim for free hardware, software and
+ minimalism. In this talk I will discuss minimalism in a broad context
+ and narrow down on what the free software community can aim for.
- 17:30 Rencontre Logiciels Libres
- 20:30 17 rue Bellegarde, Toulouse, Occitanie, France
- L’association Toulibre organise une rencontre autour des
- Logiciels Libres le mercredi 19 avril 2017, de 19h30 à 22h30 au
- Centre Culturel Bellegarde, 17 rue Bellegarde à Toulouse.
+2019-02-03
- 19:00 Rencontre Tetalab
- 21:00 12 rue Ferdinand Lassalle, Toulouse, Occitanie, France
- Rencontre hebdomadaire des hackers et artistes libristes
- Toulousains.
+07:55 Microkernel virtualization under one roof
+08:30 AW1.121
+ Today's off-the-shell virtualization solution is ridden with
+ complexity. Application of virtualization call for trustworthy
+ solutions. Complexity defeats trust.Microkernels with virtualization
+ extensions and user-level VMMs on top are a approach to mitigate
+ complexity. Modern microkernels like seL4, the NOVA microhypervisor,
+ Genode's -hw- kernel or Fiasco.OC are such promising candidates.
+ Fortunately and unfortunately, the diversity come with fragmentation
+ of the small microkernel community. There are several VMMs for each
+ platform tight to a specific microkernel, rendering it unusable
+ across various kernels.Genode supports several kernels already, so
+ that unification of virtualization interfaces for VMMs across kernels
+ seem to come into reach. Does it ? The talk will cover the venture
+ and current state of harmonization hardware-assisted virtualization
+ interfaces to fit into the Genode OS framework.
- 20 16:00 Soirée Cozy Cloud
- 18:00 123 boulevard Louis Blanc, La Roche-sur-Yon, Pays de la Loire, France
- Le 20 Avril 2017, K’ Rément Libre et LabOuest vous proposent
- de venir découvrir Cozy.
+14:40 FOSDEM infrastructure review
+14:55 H.2215 (Ferrer)
+ Informational and fun.
+
+15:00 2019 - Fifty years of Unix and Linux advances
+15:50 Janson
+ 2019 marks the fiftieth anniversary of Unix, but it is also the
+ fiftieth anniversary of the ArpaNet/Internet, and people walking on
+ the moon. It marks the 50th anniversary of Woodstock, the beginning
+ of America's LGBTQ movement at the Stonewall Inn in New York City,
+ and maddog wrote his first program fifty years ago. It was also in
+ 1969 that he shaved for the last time.2019 marks the 30th year of the
+ World Wide Web, the 25th anniversary of V1.0 of the Linux kernel, and
+ of many GNU/Linux distributions starting. 2019 also marks the
+ twentieth anniversary of the Linux Professional Institute.All of
+ these years, and anniversaries.....but why has Unix (and its younger
+ offspring Linux) lasted so long? What was different about Unix that
+ caused it to survive and flourish? Why is it important today, and
+ how can we take it further? How should we celebrate 2019? While
+ maddog does not have all the answers, he tries to make the answers he
+ does have interesting and fun to know.
+
+15:55 Closing FOSDEM 2019
+16:00 Janson
+ Some closing words. Don't miss it!
-[1]: https://tools.ietf.org/rfc/rfc5545.txt
-[2]: https://www.agendadulibre.org
DIR diff --git a/doc/rfc5545.txt b/doc/rfc5545.txt
@@ -1,9411 +0,0 @@
-
-
-
-
-
-
-Network Working Group B. Desruisseaux, Ed.
-Request for Comments: 5545 Oracle
-Obsoletes: 2445 September 2009
-Category: Standards Track
-
-
- Internet Calendaring and Scheduling Core Object Specification
- (iCalendar)
-
-Abstract
-
-This document defines the iCalendar data format for representing and
-exchanging calendaring and scheduling information such as events,
-to-dos, journal entries, and free/busy information, independent of any
-particular calendar service or protocol.
-
-Status of This Memo
-
- This document specifies an Internet standards track protocol for the
- Internet community, and requests discussion and suggestions for
- improvements. Please refer to the current edition of the "Internet
- Official Protocol Standards" (STD 1) for the standardization state
- and status of this protocol. Distribution of this memo is unlimited.
-
-Copyright and License Notice
-
- Copyright (c) 2009 IETF Trust and the persons identified as the
- document authors. All rights reserved.
-
- This document is subject to BCP 78 and the IETF Trust's Legal
- Provisions Relating to IETF Documents
- (http://trustee.ietf.org/license-info) in effect on the date of
- publication of this document. Please review these documents
- carefully, as they describe your rights and restrictions with respect
- to this document. Code Components extracted from this document must
- include Simplified BSD License text as described in Section 4.e of
- the Trust Legal Provisions and are provided without warranty as
- described in the BSD License.
-
- This document may contain material from IETF Documents or IETF
- Contributions published or made publicly available before November
- 10, 2008. The person(s) controlling the copyright in some of this
- material may not have granted the IETF Trust the right to allow
- modifications of such material outside the IETF Standards Process.
- Without obtaining an adequate license from the person(s) controlling
- the copyright in such materials, this document may not be modified
- outside the IETF Standards Process, and derivative works of it may
- not be created outside the IETF Standards Process, except to format
-
-
-
-Desruisseaux Standards Track [Page 1]
-
-RFC 5545 iCalendar September 2009
-
-
- it for publication as an RFC or to translate it into languages other
- than English.
-
-Table of Contents
-
- 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 5
- 2. Basic Grammar and Conventions . . . . . . . . . . . . . . . . 6
- 2.1. Formatting Conventions . . . . . . . . . . . . . . . . . 6
- 2.2. Related Memos . . . . . . . . . . . . . . . . . . . . . . 7
- 3. iCalendar Object Specification . . . . . . . . . . . . . . . 8
- 3.1. Content Lines . . . . . . . . . . . . . . . . . . . . . . 8
- 3.1.1. List and Field Separators . . . . . . . . . . . . . . 11
- 3.1.2. Multiple Values . . . . . . . . . . . . . . . . . . . 11
- 3.1.3. Binary Content . . . . . . . . . . . . . . . . . . . 11
- 3.1.4. Character Set . . . . . . . . . . . . . . . . . . . . 12
- 3.2. Property Parameters . . . . . . . . . . . . . . . . . . . 12
- 3.2.1. Alternate Text Representation . . . . . . . . . . . . 13
- 3.2.2. Common Name . . . . . . . . . . . . . . . . . . . . . 15
- 3.2.3. Calendar User Type . . . . . . . . . . . . . . . . . 15
- 3.2.4. Delegators . . . . . . . . . . . . . . . . . . . . . 16
- 3.2.5. Delegatees . . . . . . . . . . . . . . . . . . . . . 16
- 3.2.6. Directory Entry Reference . . . . . . . . . . . . . . 17
- 3.2.7. Inline Encoding . . . . . . . . . . . . . . . . . . . 17
- 3.2.8. Format Type . . . . . . . . . . . . . . . . . . . . . 18
- 3.2.9. Free/Busy Time Type . . . . . . . . . . . . . . . . . 19
- 3.2.10. Language . . . . . . . . . . . . . . . . . . . . . . 20
- 3.2.11. Group or List Membership . . . . . . . . . . . . . . 20
- 3.2.12. Participation Status . . . . . . . . . . . . . . . . 21
- 3.2.13. Recurrence Identifier Range . . . . . . . . . . . . . 22
- 3.2.14. Alarm Trigger Relationship . . . . . . . . . . . . . 23
- 3.2.15. Relationship Type . . . . . . . . . . . . . . . . . . 24
- 3.2.16. Participation Role . . . . . . . . . . . . . . . . . 25
- 3.2.17. RSVP Expectation . . . . . . . . . . . . . . . . . . 25
- 3.2.18. Sent By . . . . . . . . . . . . . . . . . . . . . . . 26
- 3.2.19. Time Zone Identifier . . . . . . . . . . . . . . . . 26
- 3.2.20. Value Data Types . . . . . . . . . . . . . . . . . . 28
- 3.3. Property Value Data Types . . . . . . . . . . . . . . . . 29
- 3.3.1. Binary . . . . . . . . . . . . . . . . . . . . . . . 29
- 3.3.2. Boolean . . . . . . . . . . . . . . . . . . . . . . . 30
- 3.3.3. Calendar User Address . . . . . . . . . . . . . . . . 30
- 3.3.4. Date . . . . . . . . . . . . . . . . . . . . . . . . 31
- 3.3.5. Date-Time . . . . . . . . . . . . . . . . . . . . . . 31
- 3.3.6. Duration . . . . . . . . . . . . . . . . . . . . . . 34
- 3.3.7. Float . . . . . . . . . . . . . . . . . . . . . . . . 35
- 3.3.8. Integer . . . . . . . . . . . . . . . . . . . . . . . 35
- 3.3.9. Period of Time . . . . . . . . . . . . . . . . . . . 36
- 3.3.10. Recurrence Rule . . . . . . . . . . . . . . . . . . . 37
- 3.3.11. Text . . . . . . . . . . . . . . . . . . . . . . . . 45
-
-
-
-Desruisseaux Standards Track [Page 2]
-
-RFC 5545 iCalendar September 2009
-
-
- 3.3.12. Time . . . . . . . . . . . . . . . . . . . . . . . . 46
- 3.3.13. URI . . . . . . . . . . . . . . . . . . . . . . . . . 48
- 3.3.14. UTC Offset . . . . . . . . . . . . . . . . . . . . . 49
- 3.4. iCalendar Object . . . . . . . . . . . . . . . . . . . . 49
- 3.5. Property . . . . . . . . . . . . . . . . . . . . . . . . 50
- 3.6. Calendar Components . . . . . . . . . . . . . . . . . . . 50
- 3.6.1. Event Component . . . . . . . . . . . . . . . . . . . 52
- 3.6.2. To-Do Component . . . . . . . . . . . . . . . . . . . 56
- 3.6.3. Journal Component . . . . . . . . . . . . . . . . . . 58
- 3.6.4. Free/Busy Component . . . . . . . . . . . . . . . . . 60
- 3.6.5. Time Zone Component . . . . . . . . . . . . . . . . . 63
- 3.6.6. Alarm Component . . . . . . . . . . . . . . . . . . . 72
- 3.7. Calendar Properties . . . . . . . . . . . . . . . . . . . 77
- 3.7.1. Calendar Scale . . . . . . . . . . . . . . . . . . . 77
- 3.7.2. Method . . . . . . . . . . . . . . . . . . . . . . . 78
- 3.7.3. Product Identifier . . . . . . . . . . . . . . . . . 79
- 3.7.4. Version . . . . . . . . . . . . . . . . . . . . . . . 80
- 3.8. Component Properties . . . . . . . . . . . . . . . . . . 81
- 3.8.1. Descriptive Component Properties . . . . . . . . . . 81
- 3.8.1.1. Attachment . . . . . . . . . . . . . . . . . . . 81
- 3.8.1.2. Categories . . . . . . . . . . . . . . . . . . . 82
- 3.8.1.3. Classification . . . . . . . . . . . . . . . . . 83
- 3.8.1.4. Comment . . . . . . . . . . . . . . . . . . . . . 84
- 3.8.1.5. Description . . . . . . . . . . . . . . . . . . . 85
- 3.8.1.6. Geographic Position . . . . . . . . . . . . . . . 87
- 3.8.1.7. Location . . . . . . . . . . . . . . . . . . . . 88
- 3.8.1.8. Percent Complete . . . . . . . . . . . . . . . . 89
- 3.8.1.9. Priority . . . . . . . . . . . . . . . . . . . . 90
- 3.8.1.10. Resources . . . . . . . . . . . . . . . . . . . . 92
- 3.8.1.11. Status . . . . . . . . . . . . . . . . . . . . . 93
- 3.8.1.12. Summary . . . . . . . . . . . . . . . . . . . . . 94
- 3.8.2. Date and Time Component Properties . . . . . . . . . 95
- 3.8.2.1. Date-Time Completed . . . . . . . . . . . . . . . 95
- 3.8.2.2. Date-Time End . . . . . . . . . . . . . . . . . . 96
- 3.8.2.3. Date-Time Due . . . . . . . . . . . . . . . . . . 97
- 3.8.2.4. Date-Time Start . . . . . . . . . . . . . . . . . 99
- 3.8.2.5. Duration . . . . . . . . . . . . . . . . . . . . 100
- 3.8.2.6. Free/Busy Time . . . . . . . . . . . . . . . . . 101
- 3.8.2.7. Time Transparency . . . . . . . . . . . . . . . . 102
- 3.8.3. Time Zone Component Properties . . . . . . . . . . . 103
- 3.8.3.1. Time Zone Identifier . . . . . . . . . . . . . . 103
- 3.8.3.2. Time Zone Name . . . . . . . . . . . . . . . . . 105
- 3.8.3.3. Time Zone Offset From . . . . . . . . . . . . . . 106
- 3.8.3.4. Time Zone Offset To . . . . . . . . . . . . . . . 106
- 3.8.3.5. Time Zone URL . . . . . . . . . . . . . . . . . . 107
- 3.8.4. Relationship Component Properties . . . . . . . . . . 108
- 3.8.4.1. Attendee . . . . . . . . . . . . . . . . . . . . 108
- 3.8.4.2. Contact . . . . . . . . . . . . . . . . . . . . . 111
-
-
-
-Desruisseaux Standards Track [Page 3]
-
-RFC 5545 iCalendar September 2009
-
-
- 3.8.4.3. Organizer . . . . . . . . . . . . . . . . . . . . 113
- 3.8.4.4. Recurrence ID . . . . . . . . . . . . . . . . . . 114
- 3.8.4.5. Related To . . . . . . . . . . . . . . . . . . . 117
- 3.8.4.6. Uniform Resource Locator . . . . . . . . . . . . 118
- 3.8.4.7. Unique Identifier . . . . . . . . . . . . . . . . 119
- 3.8.5. Recurrence Component Properties . . . . . . . . . . . 120
- 3.8.5.1. Exception Date-Times . . . . . . . . . . . . . . 120
- 3.8.5.2. Recurrence Date-Times . . . . . . . . . . . . . . 122
- 3.8.5.3. Recurrence Rule . . . . . . . . . . . . . . . . . 124
- 3.8.6. Alarm Component Properties . . . . . . . . . . . . . 134
- 3.8.6.1. Action . . . . . . . . . . . . . . . . . . . . . 134
- 3.8.6.2. Repeat Count . . . . . . . . . . . . . . . . . . 135
- 3.8.6.3. Trigger . . . . . . . . . . . . . . . . . . . . . 135
- 3.8.7. Change Management Component Properties . . . . . . . 138
- 3.8.7.1. Date-Time Created . . . . . . . . . . . . . . . . 138
- 3.8.7.2. Date-Time Stamp . . . . . . . . . . . . . . . . . 139
- 3.8.7.3. Last Modified . . . . . . . . . . . . . . . . . . 140
- 3.8.7.4. Sequence Number . . . . . . . . . . . . . . . . . 141
- 3.8.8. Miscellaneous Component Properties . . . . . . . . . 142
- 3.8.8.1. IANA Properties . . . . . . . . . . . . . . . . . 142
- 3.8.8.2. Non-Standard Properties . . . . . . . . . . . . . 142
- 3.8.8.3. Request Status . . . . . . . . . . . . . . . . . 144
- 4. iCalendar Object Examples . . . . . . . . . . . . . . . . . . 146
- 5. Recommended Practices . . . . . . . . . . . . . . . . . . . . 150
- 6. Internationalization Considerations . . . . . . . . . . . . . 151
- 7. Security Considerations . . . . . . . . . . . . . . . . . . . 151
- 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 151
- 8.1. iCalendar Media Type Registration . . . . . . . . . . . . 151
- 8.2. New iCalendar Elements Registration . . . . . . . . . . . 155
- 8.2.1. iCalendar Elements Registration Procedure . . . . . . 155
- 8.2.2. Registration Template for Components . . . . . . . . 155
- 8.2.3. Registration Template for Properties . . . . . . . . 156
- 8.2.4. Registration Template for Parameters . . . . . . . . 156
- 8.2.5. Registration Template for Value Data Types . . . . . 157
- 8.2.6. Registration Template for Values . . . . . . . . . . 157
- 8.3. Initial iCalendar Elements Registries . . . . . . . . . . 158
- 8.3.1. Components Registry . . . . . . . . . . . . . . . . . 158
- 8.3.2. Properties Registry . . . . . . . . . . . . . . . . . 158
- 8.3.3. Parameters Registry . . . . . . . . . . . . . . . . . 161
- 8.3.4. Value Data Types Registry . . . . . . . . . . . . . . 162
- 8.3.5. Calendar User Types Registry . . . . . . . . . . . . 162
- 8.3.6. Free/Busy Time Types Registry . . . . . . . . . . . . 163
- 8.3.7. Participation Statuses Registry . . . . . . . . . . . 163
- 8.3.8. Relationship Types Registry . . . . . . . . . . . . . 164
- 8.3.9. Participation Roles Registry . . . . . . . . . . . . 164
- 8.3.10. Actions Registry . . . . . . . . . . . . . . . . . . 165
- 8.3.11. Classifications Registry . . . . . . . . . . . . . . 165
- 8.3.12. Methods Registry . . . . . . . . . . . . . . . . . . 165
-
-
-
-Desruisseaux Standards Track [Page 4]
-
-RFC 5545 iCalendar September 2009
-
-
- 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 165
- 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 166
- 10.1. Normative References . . . . . . . . . . . . . . . . . . 166
- 10.2. Informative References . . . . . . . . . . . . . . . . . 167
- Appendix A. Differences from RFC 2445 . . . . . . . . . . . . . 169
- A.1. New Restrictions . . . . . . . . . . . . . . . . . . . . 169
- A.2. Restrictions Removed . . . . . . . . . . . . . . . . . . 169
- A.3. Deprecated Features . . . . . . . . . . . . . . . . . . . 169
-
-1. Introduction
-
- The use of calendaring and scheduling has grown considerably in the
- last decade. Enterprise and inter-enterprise business has become
- dependent on rapid scheduling of events and actions using this
- information technology. This memo is intended to progress the level
- of interoperability possible between dissimilar calendaring and
- scheduling applications. This memo defines a MIME content type for
- exchanging electronic calendaring and scheduling information. The
- Internet Calendaring and Scheduling Core Object Specification, or
- iCalendar, allows for the capture and exchange of information
- normally stored within a calendaring and scheduling application; such
- as a Personal Information Manager (PIM) or a Group-Scheduling
- product.
-
- The iCalendar format is suitable as an exchange format between
- applications or systems. The format is defined in terms of a MIME
- content type. This will enable the object to be exchanged using
- several transports, including but not limited to SMTP, HTTP, a file
- system, desktop interactive protocols such as the use of a memory-
- based clipboard or drag/drop interactions, point-to-point
- asynchronous communication, wired-network transport, or some form of
- unwired transport such as infrared.
-
- The memo also provides for the definition of iCalendar object methods
- that will map this content type to a set of messages for supporting
- calendaring and scheduling operations such as requesting, replying
- to, modifying, and canceling meetings or appointments, to-dos, and
- journal entries. The iCalendar object methods can be used to define
- other calendaring and scheduling operations such as requesting for
- and replying with free/busy time data. Such a scheduling protocol is
- defined in the iCalendar Transport-independent Interoperability
- Protocol (iTIP) defined in [2446bis].
-
- The memo also includes a formal grammar for the content type based on
- the Internet ABNF defined in [RFC5234]. This ABNF is required for
- the implementation of parsers and to serve as the definitive
- reference when ambiguities or questions arise in interpreting the
- descriptive prose definition of the memo. Additional restrictions
-
-
-
-Desruisseaux Standards Track [Page 5]
-
-RFC 5545 iCalendar September 2009
-
-
- that could not easily be expressed with the ABNF syntax are specified
- as comments in the ABNF. Comments with normative statements should
- be treated as such.
-
-2. Basic Grammar and Conventions
-
- The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
- "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
- document are to be interpreted as described in [RFC2119].
-
- This memo makes use of both a descriptive prose and a more formal
- notation for defining the calendaring and scheduling format.
-
- The notation used in this memo is the ABNF notation of [RFC5234].
- Readers intending on implementing the format defined in this memo
- should be familiar with this notation in order to properly interpret
- the specifications of this memo.
-
- All numeric values used in this memo are given in decimal notation.
-
- All names of properties, property parameters, enumerated property
- values, and property parameter values are case-insensitive. However,
- all other property values are case-sensitive, unless otherwise
- stated.
-
- Note: All indented editorial notes, such as this one, are intended
- to provide the reader with additional information. The
- information is not essential to the building of an implementation
- conformant with this memo. The information is provided to
- highlight a particular feature or characteristic of the memo.
-
- The format for the iCalendar object is based on the syntax of the
- text/directory media type [RFC2425]. While the iCalendar object is
- not a profile of the text/directory media type [RFC2425], it does
- reuse a number of the elements from the [RFC2425] specification.
-
-2.1. Formatting Conventions
-
- The elements defined in this memo are defined in prose. Many of the
- terms used to describe these have common usage that is different than
- the standards usage of this memo. In order to reference, within this
- memo, elements of the calendaring and scheduling model, core object
- (this memo), or interoperability protocol [2446bis] some formatting
- conventions have been used. Calendaring and scheduling roles are
- referred to in quoted-strings of text with the first character of
- each word in uppercase. For example, "Organizer" refers to a role of
- a "Calendar User" within the scheduling protocol defined by
- [2446bis]. Calendar components defined by this memo are referred to
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- with capitalized, quoted-strings of text. All calendar components
- start with the letter "V". For example, "VEVENT" refers to the event
- calendar component, "VTODO" refers to the to-do calendar component,
- and "VJOURNAL" refers to the daily journal calendar component.
- Scheduling methods defined by iTIP [2446bis] are referred to with
- capitalized, quoted-strings of text. For example, "REQUEST" refers
- to the method for requesting a scheduling calendar component be
- created or modified, and "REPLY" refers to the method a recipient of
- a request uses to update their status with the "Organizer" of the
- calendar component.
-
- The properties defined by this memo are referred to with capitalized,
- quoted-strings of text, followed by the word "property". For
- example, "ATTENDEE" property refers to the iCalendar property used to
- convey the calendar address of a calendar user. Property parameters
- defined by this memo are referred to with lowercase, quoted-strings
- of text, followed by the word "parameter". For example, "value"
- parameter refers to the iCalendar property parameter used to override
- the default value type for a property value. Enumerated values
- defined by this memo are referred to with capitalized text, either
- alone or followed by the word "value". For example, the "MINUTELY"
- value can be used with the "FREQ" component of the "RECUR" value type
- to specify repeating components based on an interval of one minute or
- more.
-
- The following table lists the different characters from the
- [US-ASCII] character set that is referenced in this document. For
- each character, the table specifies the character name used
- throughout this document, along with its US-ASCII decimal codepoint.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- +------------------------+-------------------+
- | Character name | Decimal codepoint |
- +------------------------+-------------------+
- | HTAB | 9 |
- | LF | 10 |
- | CR | 13 |
- | DQUOTE | 22 |
- | SPACE | 32 |
- | PLUS SIGN | 43 |
- | COMMA | 44 |
- | HYPHEN-MINUS | 45 |
- | PERIOD | 46 |
- | SOLIDUS | 47 |
- | COLON | 58 |
- | SEMICOLON | 59 |
- | LATIN CAPITAL LETTER N | 78 |
- | LATIN CAPITAL LETTER T | 84 |
- | LATIN CAPITAL LETTER X | 88 |
- | LATIN CAPITAL LETTER Z | 90 |
- | BACKSLASH | 92 |
- | LATIN SMALL LETTER N | 110 |
- +------------------------+-------------------+
-
-2.2. Related Memos
-
- Implementers will need to be familiar with several other memos that,
- along with this memo, form a framework for Internet calendaring and
- scheduling standards. This memo specifies a core specification of
- objects, value types, properties, and property parameters.
-
- o iTIP [2446bis] specifies an interoperability protocol for
- scheduling between different implementations;
-
- o iCalendar Message-Based Interoperability Protocol (iMIP) [2447bis]
- specifies an Internet email binding for [2446bis].
-
- This memo does not attempt to repeat the specification of concepts or
- definitions from these other memos. Where possible, references are
- made to the memo that provides for the specification of these
- concepts or definitions.
-
-3. iCalendar Object Specification
-
- The following sections define the details of a Calendaring and
- Scheduling Core Object Specification. The Calendaring and Scheduling
- Core Object is a collection of calendaring and scheduling
- information. Typically, this information will consist of an
- iCalendar stream with one or more iCalendar objects. The body of the
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- iCalendar object consists of a sequence of calendar properties and
- one or more calendar components.
-
- Section 3.1 defines the content line format; Section 3.2 defines the
- property parameter format; Section 3.3 defines the data types for
- property values; Section 3.4 defines the iCalendar object format;
- Section 3.5 defines the iCalendar property format; Section 3.6
- defines the calendar component format; Section 3.7 defines calendar
- properties; and Section 3.8 defines calendar component properties.
-
- This information is intended to be an integral part of the MIME
- content type registration. In addition, this information can be used
- independent of such content registration. In particular, this memo
- has direct applicability for use as a calendaring and scheduling
- exchange format in file-, memory-, or network-based transport
- mechanisms.
-
-3.1. Content Lines
-
- The iCalendar object is organized into individual lines of text,
- called content lines. Content lines are delimited by a line break,
- which is a CRLF sequence (CR character followed by LF character).
-
- Lines of text SHOULD NOT be longer than 75 octets, excluding the line
- break. Long content lines SHOULD be split into a multiple line
- representations using a line "folding" technique. That is, a long
- line can be split between any two characters by inserting a CRLF
- immediately followed by a single linear white-space character (i.e.,
- SPACE or HTAB). Any sequence of CRLF followed immediately by a
- single linear white-space character is ignored (i.e., removed) when
- processing the content type.
-
- For example, the line:
-
- DESCRIPTION:This is a long description that exists on a long line.
-
- Can be represented as:
-
- DESCRIPTION:This is a lo
- ng description
- that exists on a long line.
-
- The process of moving from this folded multiple-line representation
- to its single-line representation is called "unfolding". Unfolding
- is accomplished by removing the CRLF and the linear white-space
- character that immediately follows.
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- When parsing a content line, folded lines MUST first be unfolded
- according to the unfolding procedure described above.
-
- Note: It is possible for very simple implementations to generate
- improperly folded lines in the middle of a UTF-8 multi-octet
- sequence. For this reason, implementations need to unfold lines
- in such a way to properly restore the original sequence.
-
- The content information associated with an iCalendar object is
- formatted using a syntax similar to that defined by [RFC2425]. That
- is, the content information consists of CRLF-separated content lines.
-
- The following notation defines the lines of content in an iCalendar
- object:
-
- contentline = name *(";" param ) ":" value CRLF
- ; This ABNF is just a general definition for an initial parsing
- ; of the content line into its property name, parameter list,
- ; and value string
-
- ; When parsing a content line, folded lines MUST first
- ; be unfolded according to the unfolding procedure
- ; described above. When generating a content line, lines
- ; longer than 75 octets SHOULD be folded according to
- ; the folding procedure described above.
-
- name = iana-token / x-name
-
- iana-token = 1*(ALPHA / DIGIT / "-")
- ; iCalendar identifier registered with IANA
-
- x-name = "X-" [vendorid "-"] 1*(ALPHA / DIGIT / "-")
- ; Reserved for experimental use.
-
- vendorid = 3*(ALPHA / DIGIT)
- ; Vendor identification
-
- param = param-name "=" param-value *("," param-value)
- ; Each property defines the specific ABNF for the parameters
- ; allowed on the property. Refer to specific properties for
- ; precise parameter ABNF.
-
- param-name = iana-token / x-name
-
- param-value = paramtext / quoted-string
-
- paramtext = *SAFE-CHAR
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- value = *VALUE-CHAR
-
- quoted-string = DQUOTE *QSAFE-CHAR DQUOTE
-
- QSAFE-CHAR = WSP / %x21 / %x23-7E / NON-US-ASCII
- ; Any character except CONTROL and DQUOTE
-
- SAFE-CHAR = WSP / %x21 / %x23-2B / %x2D-39 / %x3C-7E
- / NON-US-ASCII
- ; Any character except CONTROL, DQUOTE, ";", ":", ","
-
- VALUE-CHAR = WSP / %x21-7E / NON-US-ASCII
- ; Any textual character
-
- NON-US-ASCII = UTF8-2 / UTF8-3 / UTF8-4
- ; UTF8-2, UTF8-3, and UTF8-4 are defined in [RFC3629]
-
- CONTROL = %x00-08 / %x0A-1F / %x7F
- ; All the controls except HTAB
-
- The property value component of a content line has a format that is
- property specific. Refer to the section describing each property for
- a definition of this format.
-
- All names of properties, property parameters, enumerated property
- values and property parameter values are case-insensitive. However,
- all other property values are case-sensitive, unless otherwise
- stated.
-
-3.1.1. List and Field Separators
-
- Some properties and parameters allow a list of values. Values in a
- list of values MUST be separated by a COMMA character. There is no
- significance to the order of values in a list. For those parameter
- values (such as those that specify URI values) that are specified in
- quoted-strings, the individual quoted-strings are separated by a
- COMMA character.
-
- Some property values are defined in terms of multiple parts. These
- structured property values MUST have their value parts separated by a
- SEMICOLON character.
-
- Some properties allow a list of parameters. Each property parameter
- in a list of property parameters MUST be separated by a SEMICOLON
- character.
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Property parameters with values containing a COLON character, a
- SEMICOLON character or a COMMA character MUST be placed in quoted
- text.
-
- For example, in the following properties, a SEMICOLON is used to
- separate property parameters from each other and a COMMA character is
- used to separate property values in a value list.
-
- ATTENDEE;RSVP=TRUE;ROLE=REQ-PARTICIPANT:mailto:
- jsmith@example.com
-
- RDATE;VALUE=DATE:19970304,19970504,19970704,19970904
-
-3.1.2. Multiple Values
-
- Some properties defined in the iCalendar object can have multiple
- values. The general rule for encoding multi-valued items is to
- simply create a new content line for each value, including the
- property name. However, it should be noted that some properties
- support encoding multiple values in a single property by separating
- the values with a COMMA character. Individual property definitions
- should be consulted for determining whether a specific property
- allows multiple values and in which of these two forms. Multi-valued
- properties MUST NOT be used to specify multiple language variants of
- the same value. Calendar applications SHOULD display all values.
-
-3.1.3. Binary Content
-
- Binary content information in an iCalendar object SHOULD be
- referenced using a URI within a property value. That is, the binary
- content information SHOULD be placed in an external MIME entity that
- can be referenced by a URI from within the iCalendar object. In
- applications where this is not feasible, binary content information
- can be included within an iCalendar object, but only after first
- encoding it into text using the "BASE64" encoding method defined in
- [RFC4648]. Inline binary content SHOULD only be used in applications
- whose special circumstances demand that an iCalendar object be
- expressed as a single entity. A property containing inline binary
- content information MUST specify the "ENCODING" property parameter.
- Binary content information placed external to the iCalendar object
- MUST be referenced by a uniform resource identifier (URI).
-
- The following example specifies an "ATTACH" property that references
- an attachment external to the iCalendar object with a URI reference:
-
- ATTACH:http://example.com/public/quarterly-report.doc
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- The following example specifies an "ATTACH" property with inline
- binary encoded content information:
-
- ATTACH;FMTTYPE=text/plain;ENCODING=BASE64;VALUE=BINARY:VGhlIH
- F1aWNrIGJyb3duIGZveCBqdW1wcyBvdmVyIHRoZSBsYXp5IGRvZy4
-
-3.1.4. Character Set
-
- There is not a property parameter to declare the charset used in a
- property value. The default charset for an iCalendar stream is UTF-8
- as defined in [RFC3629].
-
- The "charset" Content-Type parameter MUST be used in MIME transports
- to specify the charset being used.
-
-3.2. Property Parameters
-
- A property can have attributes with which it is associated. These
- "property parameters" contain meta-information about the property or
- the property value. Property parameters are provided to specify such
- information as the location of an alternate text representation for a
- property value, the language of a text property value, the value type
- of the property value, and other attributes.
-
- Property parameter values that contain the COLON, SEMICOLON, or COMMA
- character separators MUST be specified as quoted-string text values.
- Property parameter values MUST NOT contain the DQUOTE character. The
- DQUOTE character is used as a delimiter for parameter values that
- contain restricted characters or URI text. For example:
-
- DESCRIPTION;ALTREP="cid:part1.0001@example.org":The Fall'98 Wild
- Wizards Conference - - Las Vegas\, NV\, USA
-
- Property parameter values that are not in quoted-strings are case-
- insensitive.
-
- The general property parameters defined by this memo are defined by
- the following notation:
-
-
-
-
-
-
-
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- icalparameter = altrepparam ; Alternate text representation
- / cnparam ; Common name
- / cutypeparam ; Calendar user type
- / delfromparam ; Delegator
- / deltoparam ; Delegatee
- / dirparam ; Directory entry
- / encodingparam ; Inline encoding
- / fmttypeparam ; Format type
- / fbtypeparam ; Free/busy time type
- / languageparam ; Language for text
- / memberparam ; Group or list membership
- / partstatparam ; Participation status
- / rangeparam ; Recurrence identifier range
- / trigrelparam ; Alarm trigger relationship
- / reltypeparam ; Relationship type
- / roleparam ; Participation role
- / rsvpparam ; RSVP expectation
- / sentbyparam ; Sent by
- / tzidparam ; Reference to time zone object
- / valuetypeparam ; Property value data type
- / other-param
-
- other-param = (iana-param / x-param)
-
- iana-param = iana-token "=" param-value *("," param-value)
- ; Some other IANA-registered iCalendar parameter.
-
- x-param = x-name "=" param-value *("," param-value)
- ; A non-standard, experimental parameter.
-
- Applications MUST ignore x-param and iana-param values they don't
- recognize.
-
-3.2.1. Alternate Text Representation
-
- Parameter Name: ALTREP
-
- Purpose: To specify an alternate text representation for the
- property value.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- altrepparam = "ALTREP" "=" DQUOTE uri DQUOTE
-
- Description: This parameter specifies a URI that points to an
- alternate representation for a textual property value. A property
- specifying this parameter MUST also include a value that reflects
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- the default representation of the text value. The URI parameter
- value MUST be specified in a quoted-string.
-
- Note: While there is no restriction imposed on the URI schemes
- allowed for this parameter, Content Identifier (CID) [RFC2392],
- HTTP [RFC2616], and HTTPS [RFC2818] are the URI schemes most
- commonly used by current implementations.
-
- Example:
-
- DESCRIPTION;ALTREP="CID:part3.msg.970415T083000@example.com":
- Project XYZ Review Meeting will include the following agenda
- items: (a) Market Overview\, (b) Finances\, (c) Project Man
- agement
-
- The "ALTREP" property parameter value might point to a "text/html"
- content portion.
-
- Content-Type:text/html
- Content-Id:<part3.msg.970415T083000@example.com>
-
- <html>
- <head>
- <title></title>
- </head>
- <body>
- <p>
- <b>Project XYZ Review Meeting</b> will include
- the following agenda items:
- <ol>
- <li>Market Overview</li>
- <li>Finances</li>
- <li>Project Management</li>
- </ol>
- </p>
- </body>
- </html>
-
-3.2.2. Common Name
-
- Parameter Name: CN
-
- Purpose: To specify the common name to be associated with the
- calendar user specified by the property.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
-
-
-
-Desruisseaux Standards Track [Page 15]
-
-RFC 5545 iCalendar September 2009
-
-
- cnparam = "CN" "=" param-value
-
- Description: This parameter can be specified on properties with a
- CAL-ADDRESS value type. The parameter specifies the common name
- to be associated with the calendar user specified by the property.
- The parameter value is text. The parameter value can be used for
- display text to be associated with the calendar address specified
- by the property.
-
- Example:
-
- ORGANIZER;CN="John Smith":mailto:jsmith@example.com
-
-3.2.3. Calendar User Type
-
- Parameter Name: CUTYPE
-
- Purpose: To identify the type of calendar user specified by the
- property.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- cutypeparam = "CUTYPE" "="
- ("INDIVIDUAL" ; An individual
- / "GROUP" ; A group of individuals
- / "RESOURCE" ; A physical resource
- / "ROOM" ; A room resource
- / "UNKNOWN" ; Otherwise not known
- / x-name ; Experimental type
- / iana-token) ; Other IANA-registered
- ; type
- ; Default is INDIVIDUAL
-
- Description: This parameter can be specified on properties with a
- CAL-ADDRESS value type. The parameter identifies the type of
- calendar user specified by the property. If not specified on a
- property that allows this parameter, the default is INDIVIDUAL.
- Applications MUST treat x-name and iana-token values they don't
- recognize the same way as they would the UNKNOWN value.
-
- Example:
-
- ATTENDEE;CUTYPE=GROUP:mailto:ietf-calsch@example.org
-
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
-3.2.4. Delegators
-
- Parameter Name: DELEGATED-FROM
-
- Purpose: To specify the calendar users that have delegated their
- participation to the calendar user specified by the property.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- delfromparam = "DELEGATED-FROM" "=" DQUOTE cal-address
- DQUOTE *("," DQUOTE cal-address DQUOTE)
-
- Description: This parameter can be specified on properties with a
- CAL-ADDRESS value type. This parameter specifies those calendar
- users that have delegated their participation in a group-scheduled
- event or to-do to the calendar user specified by the property.
- The individual calendar address parameter values MUST each be
- specified in a quoted-string.
-
- Example:
-
- ATTENDEE;DELEGATED-FROM="mailto:jsmith@example.com":mailto:
- jdoe@example.com
-
-3.2.5. Delegatees
-
- Parameter Name: DELEGATED-TO
-
- Purpose: To specify the calendar users to whom the calendar user
- specified by the property has delegated participation.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- deltoparam = "DELEGATED-TO" "=" DQUOTE cal-address DQUOTE
- *("," DQUOTE cal-address DQUOTE)
-
- Description: This parameter can be specified on properties with a
- CAL-ADDRESS value type. This parameter specifies those calendar
- users whom have been delegated participation in a group-scheduled
- event or to-do by the calendar user specified by the property.
- The individual calendar address parameter values MUST each be
- specified in a quoted-string.
-
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Example:
-
- ATTENDEE;DELEGATED-TO="mailto:jdoe@example.com","mailto:jqpublic
- @example.com":mailto:jsmith@example.com
-
-3.2.6. Directory Entry Reference
-
- Parameter Name: DIR
-
- Purpose: To specify reference to a directory entry associated with
- the calendar user specified by the property.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- dirparam = "DIR" "=" DQUOTE uri DQUOTE
-
- Description: This parameter can be specified on properties with a
- CAL-ADDRESS value type. The parameter specifies a reference to
- the directory entry associated with the calendar user specified by
- the property. The parameter value is a URI. The URI parameter
- value MUST be specified in a quoted-string.
-
- Note: While there is no restriction imposed on the URI schemes
- allowed for this parameter, CID [RFC2392], DATA [RFC2397], FILE
- [RFC1738], FTP [RFC1738], HTTP [RFC2616], HTTPS [RFC2818], LDAP
- [RFC4516], and MID [RFC2392] are the URI schemes most commonly
- used by current implementations.
-
- Example:
-
- ORGANIZER;DIR="ldap://example.com:6666/o=ABC%20Industries,
- c=US???(cn=Jim%20Dolittle)":mailto:jimdo@example.com
-
-3.2.7. Inline Encoding
-
- Parameter Name: ENCODING
-
- Purpose: To specify an alternate inline encoding for the property
- value.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
-
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- encodingparam = "ENCODING" "="
- ( "8BIT"
- ; "8bit" text encoding is defined in [RFC2045]
- / "BASE64"
- ; "BASE64" binary encoding format is defined in [RFC4648]
- )
-
- Description: This property parameter identifies the inline encoding
- used in a property value. The default encoding is "8BIT",
- corresponding to a property value consisting of text. The
- "BASE64" encoding type corresponds to a property value encoded
- using the "BASE64" encoding defined in [RFC2045].
-
- If the value type parameter is ";VALUE=BINARY", then the inline
- encoding parameter MUST be specified with the value
- ";ENCODING=BASE64".
-
- Example:
-
- ATTACH;FMTTYPE=text/plain;ENCODING=BASE64;VALUE=BINARY:TG9yZW
- 0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2ljaW
- 5nIGVsaXQsIHNlZCBkbyBlaXVzbW9kIHRlbXBvciBpbmNpZGlkdW50IHV0IG
- xhYm9yZSBldCBkb2xvcmUgbWFnbmEgYWxpcXVhLiBVdCBlbmltIGFkIG1pbm
- ltIHZlbmlhbSwgcXVpcyBub3N0cnVkIGV4ZXJjaXRhdGlvbiB1bGxhbWNvIG
- xhYm9yaXMgbmlzaSB1dCBhbGlxdWlwIGV4IGVhIGNvbW1vZG8gY29uc2VxdW
- F0LiBEdWlzIGF1dGUgaXJ1cmUgZG9sb3IgaW4gcmVwcmVoZW5kZXJpdCBpbi
- B2b2x1cHRhdGUgdmVsaXQgZXNzZSBjaWxsdW0gZG9sb3JlIGV1IGZ1Z2lhdC
- BudWxsYSBwYXJpYXR1ci4gRXhjZXB0ZXVyIHNpbnQgb2NjYWVjYXQgY3VwaW
- RhdGF0IG5vbiBwcm9pZGVudCwgc3VudCBpbiBjdWxwYSBxdWkgb2ZmaWNpYS
- BkZXNlcnVudCBtb2xsaXQgYW5pbSBpZCBlc3QgbGFib3J1bS4=
-
-3.2.8. Format Type
-
- Parameter Name: FMTTYPE
-
- Purpose: To specify the content type of a referenced object.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- fmttypeparam = "FMTTYPE" "=" type-name "/" subtype-name
- ; Where "type-name" and "subtype-name" are
- ; defined in Section 4.2 of [RFC4288].
-
- Description: This parameter can be specified on properties that are
- used to reference an object. The parameter specifies the media
- type [RFC4288] of the referenced object. For example, on the
- "ATTACH" property, an FTP type URI value does not, by itself,
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- necessarily convey the type of content associated with the
- resource. The parameter value MUST be the text for either an
- IANA-registered media type or a non-standard media type.
-
- Example:
-
- ATTACH;FMTTYPE=application/msword:ftp://example.com/pub/docs/
- agenda.doc
-
-3.2.9. Free/Busy Time Type
-
- Parameter Name: FBTYPE
-
- Purpose: To specify the free or busy time type.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- fbtypeparam = "FBTYPE" "=" ("FREE" / "BUSY"
- / "BUSY-UNAVAILABLE" / "BUSY-TENTATIVE"
- / x-name
- ; Some experimental iCalendar free/busy type.
- / iana-token)
- ; Some other IANA-registered iCalendar free/busy type.
-
- Description: This parameter specifies the free or busy time type.
- The value FREE indicates that the time interval is free for
- scheduling. The value BUSY indicates that the time interval is
- busy because one or more events have been scheduled for that
- interval. The value BUSY-UNAVAILABLE indicates that the time
- interval is busy and that the interval can not be scheduled. The
- value BUSY-TENTATIVE indicates that the time interval is busy
- because one or more events have been tentatively scheduled for
- that interval. If not specified on a property that allows this
- parameter, the default is BUSY. Applications MUST treat x-name
- and iana-token values they don't recognize the same way as they
- would the BUSY value.
-
- Example: The following is an example of this parameter on a
- "FREEBUSY" property.
-
- FREEBUSY;FBTYPE=BUSY:19980415T133000Z/19980415T170000Z
-
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-3.2.10. Language
-
- Parameter Name: LANGUAGE
-
- Purpose: To specify the language for text values in a property or
- property parameter.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- languageparam = "LANGUAGE" "=" language
-
- language = Language-Tag
- ; As defined in [RFC5646].
-
- Description: This parameter identifies the language of the text in
- the property value and of all property parameter values of the
- property. The value of the "LANGUAGE" property parameter is that
- defined in [RFC5646].
-
- For transport in a MIME entity, the Content-Language header field
- can be used to set the default language for the entire body part.
- Otherwise, no default language is assumed.
-
- Example: The following are examples of this parameter on the
- "SUMMARY" and "LOCATION" properties:
-
- SUMMARY;LANGUAGE=en-US:Company Holiday Party
-
- LOCATION;LANGUAGE=en:Germany
-
- LOCATION;LANGUAGE=no:Tyskland
-
-3.2.11. Group or List Membership
-
- Parameter Name: MEMBER
-
- Purpose: To specify the group or list membership of the calendar
- user specified by the property.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- memberparam = "MEMBER" "=" DQUOTE cal-address DQUOTE
- *("," DQUOTE cal-address DQUOTE)
-
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- Description: This parameter can be specified on properties with a
- CAL-ADDRESS value type. The parameter identifies the groups or
- list membership for the calendar user specified by the property.
- The parameter value is either a single calendar address in a
- quoted-string or a COMMA-separated list of calendar addresses,
- each in a quoted-string. The individual calendar address
- parameter values MUST each be specified in a quoted-string.
-
- Example:
-
- ATTENDEE;MEMBER="mailto:ietf-calsch@example.org":mailto:
- jsmith@example.com
-
- ATTENDEE;MEMBER="mailto:projectA@example.com","mailto:pr
- ojectB@example.com":mailto:janedoe@example.com
-
-3.2.12. Participation Status
-
- Parameter Name: PARTSTAT
-
- Purpose: To specify the participation status for the calendar user
- specified by the property.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- partstatparam = "PARTSTAT" "="
- (partstat-event
- / partstat-todo
- / partstat-jour)
-
- partstat-event = ("NEEDS-ACTION" ; Event needs action
- / "ACCEPTED" ; Event accepted
- / "DECLINED" ; Event declined
- / "TENTATIVE" ; Event tentatively
- ; accepted
- / "DELEGATED" ; Event delegated
- / x-name ; Experimental status
- / iana-token) ; Other IANA-registered
- ; status
- ; These are the participation statuses for a "VEVENT".
- ; Default is NEEDS-ACTION.
-
- partstat-todo = ("NEEDS-ACTION" ; To-do needs action
- / "ACCEPTED" ; To-do accepted
- / "DECLINED" ; To-do declined
- / "TENTATIVE" ; To-do tentatively
- ; accepted
-
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- / "DELEGATED" ; To-do delegated
- / "COMPLETED" ; To-do completed
- ; COMPLETED property has
- ; DATE-TIME completed
- / "IN-PROCESS" ; To-do in process of
- ; being completed
- / x-name ; Experimental status
- / iana-token) ; Other IANA-registered
- ; status
- ; These are the participation statuses for a "VTODO".
- ; Default is NEEDS-ACTION.
-
-
-
- partstat-jour = ("NEEDS-ACTION" ; Journal needs action
- / "ACCEPTED" ; Journal accepted
- / "DECLINED" ; Journal declined
- / x-name ; Experimental status
- / iana-token) ; Other IANA-registered
- ; status
- ; These are the participation statuses for a "VJOURNAL".
- ; Default is NEEDS-ACTION.
-
- Description: This parameter can be specified on properties with a
- CAL-ADDRESS value type. The parameter identifies the
- participation status for the calendar user specified by the
- property value. The parameter values differ depending on whether
- they are associated with a group-scheduled "VEVENT", "VTODO", or
- "VJOURNAL". The values MUST match one of the values allowed for
- the given calendar component. If not specified on a property that
- allows this parameter, the default value is NEEDS-ACTION.
- Applications MUST treat x-name and iana-token values they don't
- recognize the same way as they would the NEEDS-ACTION value.
-
- Example:
-
- ATTENDEE;PARTSTAT=DECLINED:mailto:jsmith@example.com
-
-3.2.13. Recurrence Identifier Range
-
- Parameter Name: RANGE
-
- Purpose: To specify the effective range of recurrence instances from
- the instance specified by the recurrence identifier specified by
- the property.
-
- Format Definition: This property parameter is defined by the
- following notation:
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- rangeparam = "RANGE" "=" "THISANDFUTURE"
- ; To specify the instance specified by the recurrence identifier
- ; and all subsequent recurrence instances.
-
- Description: This parameter can be specified on a property that
- specifies a recurrence identifier. The parameter specifies the
- effective range of recurrence instances that is specified by the
- property. The effective range is from the recurrence identifier
- specified by the property. If this parameter is not specified on
- an allowed property, then the default range is the single instance
- specified by the recurrence identifier value of the property. The
- parameter value can only be "THISANDFUTURE" to indicate a range
- defined by the recurrence identifier and all subsequent instances.
- The value "THISANDPRIOR" is deprecated by this revision of
- iCalendar and MUST NOT be generated by applications.
-
- Example:
-
- RECURRENCE-ID;RANGE=THISANDFUTURE:19980401T133000Z
-
-3.2.14. Alarm Trigger Relationship
-
- Parameter Name: RELATED
-
- Purpose: To specify the relationship of the alarm trigger with
- respect to the start or end of the calendar component.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- trigrelparam = "RELATED" "="
- ("START" ; Trigger off of start
- / "END") ; Trigger off of end
-
- Description: This parameter can be specified on properties that
- specify an alarm trigger with a "DURATION" value type. The
- parameter specifies whether the alarm will trigger relative to the
- start or end of the calendar component. The parameter value START
- will set the alarm to trigger off the start of the calendar
- component; the parameter value END will set the alarm to trigger
- off the end of the calendar component. If the parameter is not
- specified on an allowable property, then the default is START.
-
- Example:
-
- TRIGGER;RELATED=END:PT5M
-
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-3.2.15. Relationship Type
-
- Parameter Name: RELTYPE
-
- Purpose: To specify the type of hierarchical relationship associated
- with the calendar component specified by the property.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- reltypeparam = "RELTYPE" "="
- ("PARENT" ; Parent relationship - Default
- / "CHILD" ; Child relationship
- / "SIBLING" ; Sibling relationship
- / iana-token ; Some other IANA-registered
- ; iCalendar relationship type
- / x-name) ; A non-standard, experimental
- ; relationship type
-
- Description: This parameter can be specified on a property that
- references another related calendar. The parameter specifies the
- hierarchical relationship type of the calendar component
- referenced by the property. The parameter value can be PARENT, to
- indicate that the referenced calendar component is a superior of
- calendar component; CHILD to indicate that the referenced calendar
- component is a subordinate of the calendar component; or SIBLING
- to indicate that the referenced calendar component is a peer of
- the calendar component. If this parameter is not specified on an
- allowable property, the default relationship type is PARENT.
- Applications MUST treat x-name and iana-token values they don't
- recognize the same way as they would the PARENT value.
-
- Example:
-
- RELATED-TO;RELTYPE=SIBLING:19960401-080045-4000F192713@
- example.com
-
-3.2.16. Participation Role
-
- Parameter Name: ROLE
-
- Purpose: To specify the participation role for the calendar user
- specified by the property.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
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- roleparam = "ROLE" "="
- ("CHAIR" ; Indicates chair of the
- ; calendar entity
- / "REQ-PARTICIPANT" ; Indicates a participant whose
- ; participation is required
- / "OPT-PARTICIPANT" ; Indicates a participant whose
- ; participation is optional
- / "NON-PARTICIPANT" ; Indicates a participant who
- ; is copied for information
- ; purposes only
- / x-name ; Experimental role
- / iana-token) ; Other IANA role
- ; Default is REQ-PARTICIPANT
-
- Description: This parameter can be specified on properties with a
- CAL-ADDRESS value type. The parameter specifies the participation
- role for the calendar user specified by the property in the group
- schedule calendar component. If not specified on a property that
- allows this parameter, the default value is REQ-PARTICIPANT.
- Applications MUST treat x-name and iana-token values they don't
- recognize the same way as they would the REQ-PARTICIPANT value.
-
- Example:
-
- ATTENDEE;ROLE=CHAIR:mailto:mrbig@example.com
-
-3.2.17. RSVP Expectation
-
- Parameter Name: RSVP
-
- Purpose: To specify whether there is an expectation of a favor of a
- reply from the calendar user specified by the property value.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- rsvpparam = "RSVP" "=" ("TRUE" / "FALSE")
- ; Default is FALSE
-
- Description: This parameter can be specified on properties with a
- CAL-ADDRESS value type. The parameter identifies the expectation
- of a reply from the calendar user specified by the property value.
- This parameter is used by the "Organizer" to request a
- participation status reply from an "Attendee" of a group-scheduled
- event or to-do. If not specified on a property that allows this
- parameter, the default value is FALSE.
-
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- Example:
-
- ATTENDEE;RSVP=TRUE:mailto:jsmith@example.com
-
-3.2.18. Sent By
-
- Parameter Name: SENT-BY
-
- Purpose: To specify the calendar user that is acting on behalf of
- the calendar user specified by the property.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- sentbyparam = "SENT-BY" "=" DQUOTE cal-address DQUOTE
-
- Description: This parameter can be specified on properties with a
- CAL-ADDRESS value type. The parameter specifies the calendar user
- that is acting on behalf of the calendar user specified by the
- property. The parameter value MUST be a mailto URI as defined in
- [RFC2368]. The individual calendar address parameter values MUST
- each be specified in a quoted-string.
-
- Example:
-
- ORGANIZER;SENT-BY="mailto:sray@example.com":mailto:
- jsmith@example.com
-
-3.2.19. Time Zone Identifier
-
- Parameter Name: TZID
-
- Purpose: To specify the identifier for the time zone definition for
- a time component in the property value.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- tzidparam = "TZID" "=" [tzidprefix] paramtext
-
- tzidprefix = "/"
-
- Description: This parameter MUST be specified on the "DTSTART",
- "DTEND", "DUE", "EXDATE", and "RDATE" properties when either a
- DATE-TIME or TIME value type is specified and when the value is
- neither a UTC or a "floating" time. Refer to the DATE-TIME or
- TIME value type definition for a description of UTC and "floating
- time" formats. This property parameter specifies a text value
-
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- that uniquely identifies the "VTIMEZONE" calendar component to be
- used when evaluating the time portion of the property. The value
- of the "TZID" property parameter will be equal to the value of the
- "TZID" property for the matching time zone definition. An
- individual "VTIMEZONE" calendar component MUST be specified for
- each unique "TZID" parameter value specified in the iCalendar
- object.
-
- The parameter MUST be specified on properties with a DATE-TIME
- value if the DATE-TIME is not either a UTC or a "floating" time.
- Failure to include and follow VTIMEZONE definitions in iCalendar
- objects may lead to inconsistent understanding of the local time
- at any given location.
-
- The presence of the SOLIDUS character as a prefix, indicates that
- this "TZID" represents a unique ID in a globally defined time zone
- registry (when such registry is defined).
-
- Note: This document does not define a naming convention for
- time zone identifiers. Implementers may want to use the naming
- conventions defined in existing time zone specifications such
- as the public-domain TZ database [TZDB]. The specification of
- globally unique time zone identifiers is not addressed by this
- document and is left for future study.
-
- The following are examples of this property parameter:
-
- DTSTART;TZID=America/New_York:19980119T020000
-
- DTEND;TZID=America/New_York:19980119T030000
-
- The "TZID" property parameter MUST NOT be applied to DATE
- properties and DATE-TIME or TIME properties whose time values are
- specified in UTC.
-
- The use of local time in a DATE-TIME or TIME value without the
- "TZID" property parameter is to be interpreted as floating time,
- regardless of the existence of "VTIMEZONE" calendar components in
- the iCalendar object.
-
- For more information, see the sections on the value types DATE-
- TIME and TIME.
-
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-3.2.20. Value Data Types
-
- Parameter Name: VALUE
-
- Purpose: To explicitly specify the value type format for a property
- value.
-
- Format Definition: This property parameter is defined by the
- following notation:
-
- valuetypeparam = "VALUE" "=" valuetype
-
- valuetype = ("BINARY"
- / "BOOLEAN"
- / "CAL-ADDRESS"
- / "DATE"
- / "DATE-TIME"
- / "DURATION"
- / "FLOAT"
- / "INTEGER"
- / "PERIOD"
- / "RECUR"
- / "TEXT"
- / "TIME"
- / "URI"
- / "UTC-OFFSET"
- / x-name
- ; Some experimental iCalendar value type.
- / iana-token)
- ; Some other IANA-registered iCalendar value type.
-
- Description: This parameter specifies the value type and format of
- the property value. The property values MUST be of a single value
- type. For example, a "RDATE" property cannot have a combination
- of DATE-TIME and TIME value types.
-
- If the property's value is the default value type, then this
- parameter need not be specified. However, if the property's
- default value type is overridden by some other allowable value
- type, then this parameter MUST be specified.
-
- Applications MUST preserve the value data for x-name and iana-
- token values that they don't recognize without attempting to
- interpret or parse the value data.
-
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-3.3. Property Value Data Types
-
- The properties in an iCalendar object are strongly typed. The
- definition of each property restricts the value to be one of the
- value data types, or simply value types, defined in this section.
- The value type for a property will either be specified implicitly as
- the default value type or will be explicitly specified with the
- "VALUE" parameter. If the value type of a property is one of the
- alternate valid types, then it MUST be explicitly specified with the
- "VALUE" parameter.
-
-3.3.1. Binary
-
- Value Name: BINARY
-
- Purpose: This value type is used to identify properties that contain
- a character encoding of inline binary data. For example, an
- inline attachment of a document might be included in an iCalendar
- object.
-
- Format Definition: This value type is defined by the following
- notation:
-
- binary = *(4b-char) [b-end]
- ; A "BASE64" encoded character string, as defined by [RFC4648].
-
- b-end = (2b-char "==") / (3b-char "=")
-
- b-char = ALPHA / DIGIT / "+" / "/"
-
- Description: Property values with this value type MUST also include
- the inline encoding parameter sequence of ";ENCODING=BASE64".
- That is, all inline binary data MUST first be character encoded
- using the "BASE64" encoding method defined in [RFC2045]. No
- additional content value encoding (i.e., BACKSLASH character
- encoding, see Section 3.3.11) is defined for this value type.
-
-
-
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- Example: The following is an example of a "BASE64" encoded binary
- value data:
-
- ATTACH;FMTTYPE=image/vnd.microsoft.icon;ENCODING=BASE64;VALUE
- =BINARY:AAABAAEAEBAQAAEABAAoAQAAFgAAACgAAAAQAAAAIAAAAAEABAAA
- AAAAAAAAAAAAAAAAAAAAAAAAAAAAAACAAAAAgIAAAICAgADAwMAA////AAAA
- AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
- AAAAAAAAAAAAAAAAAAAAAAMwAAAAAAABNEMQAAAAAAAkQgAAAAAAJEREQgAA
- ACECQ0QgEgAAQxQzM0E0AABERCRCREQAADRDJEJEQwAAAhA0QwEQAAAAAERE
- AAAAAAAAREQAAAAAAAAkQgAAAAAAAAMgAAAAAAAAAAAAAAAAAAAAAAAAAAAA
- AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
- AAAAAAAAAAAA
-
-3.3.2. Boolean
-
- Value Name: BOOLEAN
-
- Purpose: This value type is used to identify properties that contain
- either a "TRUE" or "FALSE" Boolean value.
-
- Format Definition: This value type is defined by the following
- notation:
-
- boolean = "TRUE" / "FALSE"
-
- Description: These values are case-insensitive text. No additional
- content value encoding (i.e., BACKSLASH character encoding, see
- Section 3.3.11) is defined for this value type.
-
- Example: The following is an example of a hypothetical property that
- has a BOOLEAN value type:
-
- TRUE
-
-3.3.3. Calendar User Address
-
- Value Name: CAL-ADDRESS
-
- Purpose: This value type is used to identify properties that contain
- a calendar user address.
-
- Format Definition: This value type is defined by the following
- notation:
-
- cal-address = uri
-
- Description: The value is a URI as defined by [RFC3986] or any other
- IANA-registered form for a URI. When used to address an Internet
-
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- email transport address for a calendar user, the value MUST be a
- mailto URI, as defined by [RFC2368]. No additional content value
- encoding (i.e., BACKSLASH character encoding, see Section 3.3.11)
- is defined for this value type.
-
- Example:
-
- mailto:jane_doe@example.com
-
-3.3.4. Date
-
- Value Name: DATE
-
- Purpose: This value type is used to identify values that contain a
- calendar date.
-
- Format Definition: This value type is defined by the following
- notation:
-
- date = date-value
-
- date-value = date-fullyear date-month date-mday
- date-fullyear = 4DIGIT
- date-month = 2DIGIT ;01-12
- date-mday = 2DIGIT ;01-28, 01-29, 01-30, 01-31
- ;based on month/year
-
- Description: If the property permits, multiple "date" values are
- specified as a COMMA-separated list of values. The format for the
- value type is based on the [ISO.8601.2004] complete
- representation, basic format for a calendar date. The textual
- format specifies a four-digit year, two-digit month, and two-digit
- day of the month. There are no separator characters between the
- year, month, and day component text.
-
- No additional content value encoding (i.e., BACKSLASH character
- encoding, see Section 3.3.11) is defined for this value type.
-
- Example: The following represents July 14, 1997:
-
- 19970714
-
-3.3.5. Date-Time
-
- Value Name: DATE-TIME
-
- Purpose: This value type is used to identify values that specify a
- precise calendar date and time of day.
-
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- Format Definition: This value type is defined by the following
- notation:
-
- date-time = date "T" time ;As specified in the DATE and TIME
- ;value definitions
-
- Description: If the property permits, multiple "DATE-TIME" values
- are specified as a COMMA-separated list of values. No additional
- content value encoding (i.e., BACKSLASH character encoding, see
- Section 3.3.11) is defined for this value type.
-
- The "DATE-TIME" value type is used to identify values that contain
- a precise calendar date and time of day. The format is based on
- the [ISO.8601.2004] complete representation, basic format for a
- calendar date and time of day. The text format is a concatenation
- of the "date", followed by the LATIN CAPITAL LETTER T character,
- the time designator, followed by the "time" format.
-
- The "DATE-TIME" value type expresses time values in three forms:
-
- The form of date and time with UTC offset MUST NOT be used. For
- example, the following is not valid for a DATE-TIME value:
-
- 19980119T230000-0800 ;Invalid time format
-
- FORM #1: DATE WITH LOCAL TIME
-
- The date with local time form is simply a DATE-TIME value that
- does not contain the UTC designator nor does it reference a time
- zone. For example, the following represents January 18, 1998, at
- 11 PM:
-
- 19980118T230000
-
- DATE-TIME values of this type are said to be "floating" and are
- not bound to any time zone in particular. They are used to
- represent the same hour, minute, and second value regardless of
- which time zone is currently being observed. For example, an
- event can be defined that indicates that an individual will be
- busy from 11:00 AM to 1:00 PM every day, no matter which time zone
- the person is in. In these cases, a local time can be specified.
- The recipient of an iCalendar object with a property value
- consisting of a local time, without any relative time zone
- information, SHOULD interpret the value as being fixed to whatever
- time zone the "ATTENDEE" is in at any given moment. This means
- that two "Attendees", in different time zones, receiving the same
- event definition as a floating time, may be participating in the
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- event at different actual times. Floating time SHOULD only be
- used where that is the reasonable behavior.
-
- In most cases, a fixed time is desired. To properly communicate a
- fixed time in a property value, either UTC time or local time with
- time zone reference MUST be specified.
-
- The use of local time in a DATE-TIME value without the "TZID"
- property parameter is to be interpreted as floating time,
- regardless of the existence of "VTIMEZONE" calendar components in
- the iCalendar object.
-
- FORM #2: DATE WITH UTC TIME
-
- The date with UTC time, or absolute time, is identified by a LATIN
- CAPITAL LETTER Z suffix character, the UTC designator, appended to
- the time value. For example, the following represents January 19,
- 1998, at 0700 UTC:
-
- 19980119T070000Z
-
- The "TZID" property parameter MUST NOT be applied to DATE-TIME
- properties whose time values are specified in UTC.
-
- FORM #3: DATE WITH LOCAL TIME AND TIME ZONE REFERENCE
-
- The date and local time with reference to time zone information is
- identified by the use the "TZID" property parameter to reference
- the appropriate time zone definition. "TZID" is discussed in
- detail in Section 3.2.19. For example, the following represents
- 2:00 A.M. in New York on January 19, 1998:
-
- TZID=America/New_York:19980119T020000
-
- If, based on the definition of the referenced time zone, the local
- time described occurs more than once (when changing from daylight
- to standard time), the DATE-TIME value refers to the first
- occurrence of the referenced time. Thus, TZID=America/
- New_York:20071104T013000 indicates November 4, 2007 at 1:30 A.M.
- EDT (UTC-04:00). If the local time described does not occur (when
- changing from standard to daylight time), the DATE-TIME value is
- interpreted using the UTC offset before the gap in local times.
- Thus, TZID=America/New_York:20070311T023000 indicates March 11,
- 2007 at 3:30 A.M. EDT (UTC-04:00), one hour after 1:30 A.M. EST
- (UTC-05:00).
-
-
-
-
-
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-
-
- A time value MUST only specify the second 60 when specifying a
- positive leap second. For example:
-
- 19970630T235960Z
-
- Implementations that do not support leap seconds SHOULD interpret
- the second 60 as equivalent to the second 59.
-
- Example: The following represents July 14, 1997, at 1:30 PM in New
- York City in each of the three time formats, using the "DTSTART"
- property.
-
- DTSTART:19970714T133000 ; Local time
- DTSTART:19970714T173000Z ; UTC time
- DTSTART;TZID=America/New_York:19970714T133000
- ; Local time and time
- ; zone reference
-
-3.3.6. Duration
-
- Value Name: DURATION
-
- Purpose: This value type is used to identify properties that contain
- a duration of time.
-
- Format Definition: This value type is defined by the following
- notation:
-
- dur-value = (["+"] / "-") "P" (dur-date / dur-time / dur-week)
-
- dur-date = dur-day [dur-time]
- dur-time = "T" (dur-hour / dur-minute / dur-second)
- dur-week = 1*DIGIT "W"
- dur-hour = 1*DIGIT "H" [dur-minute]
- dur-minute = 1*DIGIT "M" [dur-second]
- dur-second = 1*DIGIT "S"
- dur-day = 1*DIGIT "D"
-
- Description: If the property permits, multiple "duration" values are
- specified by a COMMA-separated list of values. The format is
- based on the [ISO.8601.2004] complete representation basic format
- with designators for the duration of time. The format can
- represent nominal durations (weeks and days) and accurate
- durations (hours, minutes, and seconds). Note that unlike
- [ISO.8601.2004], this value type doesn't support the "Y" and "M"
- designators to specify durations in terms of years and months.
-
-
-
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-
- The duration of a week or a day depends on its position in the
- calendar. In the case of discontinuities in the time scale, such
- as the change from standard time to daylight time and back, the
- computation of the exact duration requires the subtraction or
- addition of the change of duration of the discontinuity. Leap
- seconds MUST NOT be considered when computing an exact duration.
- When computing an exact duration, the greatest order time
- components MUST be added first, that is, the number of days MUST
- be added first, followed by the number of hours, number of
- minutes, and number of seconds.
-
- Negative durations are typically used to schedule an alarm to
- trigger before an associated time (see Section 3.8.6.3).
-
- No additional content value encoding (i.e., BACKSLASH character
- encoding, see Section 3.3.11) are defined for this value type.
-
- Example: A duration of 15 days, 5 hours, and 20 seconds would be:
-
- P15DT5H0M20S
-
- A duration of 7 weeks would be:
-
- P7W
-
-3.3.7. Float
-
- Value Name: FLOAT
-
- Purpose: This value type is used to identify properties that contain
- a real-number value.
-
- Format Definition: This value type is defined by the following
- notation:
-
- float = (["+"] / "-") 1*DIGIT ["." 1*DIGIT]
-
- Description: If the property permits, multiple "float" values are
- specified by a COMMA-separated list of values.
-
- No additional content value encoding (i.e., BACKSLASH character
- encoding, see Section 3.3.11) is defined for this value type.
-
- Example:
-
- 1000000.0000001
- 1.333
- -3.14
-
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-
-
-3.3.8. Integer
-
- Value Name: INTEGER
-
- Purpose: This value type is used to identify properties that contain
- a signed integer value.
-
- Format Definition: This value type is defined by the following
- notation:
-
- integer = (["+"] / "-") 1*DIGIT
-
- Description: If the property permits, multiple "integer" values are
- specified by a COMMA-separated list of values. The valid range
- for "integer" is -2147483648 to 2147483647. If the sign is not
- specified, then the value is assumed to be positive.
-
- No additional content value encoding (i.e., BACKSLASH character
- encoding, see Section 3.3.11) is defined for this value type.
-
- Example:
-
- 1234567890
- -1234567890
- +1234567890
- 432109876
-
-3.3.9. Period of Time
-
- Value Name: PERIOD
-
- Purpose: This value type is used to identify values that contain a
- precise period of time.
-
- Format Definition: This value type is defined by the following
- notation:
-
- period = period-explicit / period-start
-
- period-explicit = date-time "/" date-time
- ; [ISO.8601.2004] complete representation basic format for a
- ; period of time consisting of a start and end. The start MUST
- ; be before the end.
-
- period-start = date-time "/" dur-value
- ; [ISO.8601.2004] complete representation basic format for a
- ; period of time consisting of a start and positive duration
- ; of time.
-
-
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-
- Description: If the property permits, multiple "period" values are
- specified by a COMMA-separated list of values. There are two
- forms of a period of time. First, a period of time is identified
- by its start and its end. This format is based on the
- [ISO.8601.2004] complete representation, basic format for "DATE-
- TIME" start of the period, followed by a SOLIDUS character
- followed by the "DATE-TIME" of the end of the period. The start
- of the period MUST be before the end of the period. Second, a
- period of time can also be defined by a start and a positive
- duration of time. The format is based on the [ISO.8601.2004]
- complete representation, basic format for the "DATE-TIME" start of
- the period, followed by a SOLIDUS character, followed by the
- [ISO.8601.2004] basic format for "DURATION" of the period.
-
- Example: The period starting at 18:00:00 UTC, on January 1, 1997 and
- ending at 07:00:00 UTC on January 2, 1997 would be:
-
- 19970101T180000Z/19970102T070000Z
-
- The period start at 18:00:00 on January 1, 1997 and lasting 5
- hours and 30 minutes would be:
-
- 19970101T180000Z/PT5H30M
-
- No additional content value encoding (i.e., BACKSLASH character
- encoding, see Section 3.3.11) is defined for this value type.
-
-3.3.10. Recurrence Rule
-
- Value Name: RECUR
-
- Purpose: This value type is used to identify properties that contain
- a recurrence rule specification.
-
- Format Definition: This value type is defined by the following
- notation:
-
- recur = recur-rule-part *( ";" recur-rule-part )
- ;
- ; The rule parts are not ordered in any
- ; particular sequence.
- ;
- ; The FREQ rule part is REQUIRED,
- ; but MUST NOT occur more than once.
- ;
- ; The UNTIL or COUNT rule parts are OPTIONAL,
- ; but they MUST NOT occur in the same 'recur'.
- ;
-
-
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-
-
- ; The other rule parts are OPTIONAL,
- ; but MUST NOT occur more than once.
-
- recur-rule-part = ( "FREQ" "=" freq )
- / ( "UNTIL" "=" enddate )
- / ( "COUNT" "=" 1*DIGIT )
- / ( "INTERVAL" "=" 1*DIGIT )
- / ( "BYSECOND" "=" byseclist )
- / ( "BYMINUTE" "=" byminlist )
- / ( "BYHOUR" "=" byhrlist )
- / ( "BYDAY" "=" bywdaylist )
- / ( "BYMONTHDAY" "=" bymodaylist )
- / ( "BYYEARDAY" "=" byyrdaylist )
- / ( "BYWEEKNO" "=" bywknolist )
- / ( "BYMONTH" "=" bymolist )
- / ( "BYSETPOS" "=" bysplist )
- / ( "WKST" "=" weekday )
-
- freq = "SECONDLY" / "MINUTELY" / "HOURLY" / "DAILY"
- / "WEEKLY" / "MONTHLY" / "YEARLY"
-
- enddate = date / date-time
-
- byseclist = ( seconds *("," seconds) )
-
- seconds = 1*2DIGIT ;0 to 60
-
- byminlist = ( minutes *("," minutes) )
-
- minutes = 1*2DIGIT ;0 to 59
-
- byhrlist = ( hour *("," hour) )
-
- hour = 1*2DIGIT ;0 to 23
-
- bywdaylist = ( weekdaynum *("," weekdaynum) )
-
- weekdaynum = [[plus / minus] ordwk] weekday
-
- plus = "+"
-
- minus = "-"
-
- ordwk = 1*2DIGIT ;1 to 53
-
- weekday = "SU" / "MO" / "TU" / "WE" / "TH" / "FR" / "SA"
- ;Corresponding to SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY,
- ;FRIDAY, and SATURDAY days of the week.
-
-
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-
-
- bymodaylist = ( monthdaynum *("," monthdaynum) )
-
- monthdaynum = [plus / minus] ordmoday
-
- ordmoday = 1*2DIGIT ;1 to 31
-
- byyrdaylist = ( yeardaynum *("," yeardaynum) )
-
- yeardaynum = [plus / minus] ordyrday
-
- ordyrday = 1*3DIGIT ;1 to 366
-
- bywknolist = ( weeknum *("," weeknum) )
-
- weeknum = [plus / minus] ordwk
-
- bymolist = ( monthnum *("," monthnum) )
-
- monthnum = 1*2DIGIT ;1 to 12
-
- bysplist = ( setposday *("," setposday) )
-
- setposday = yeardaynum
-
- Description: This value type is a structured value consisting of a
- list of one or more recurrence grammar parts. Each rule part is
- defined by a NAME=VALUE pair. The rule parts are separated from
- each other by the SEMICOLON character. The rule parts are not
- ordered in any particular sequence. Individual rule parts MUST
- only be specified once. Compliant applications MUST accept rule
- parts ordered in any sequence, but to ensure backward
- compatibility with applications that pre-date this revision of
- iCalendar the FREQ rule part MUST be the first rule part specified
- in a RECUR value.
-
- The FREQ rule part identifies the type of recurrence rule. This
- rule part MUST be specified in the recurrence rule. Valid values
- include SECONDLY, to specify repeating events based on an interval
- of a second or more; MINUTELY, to specify repeating events based
- on an interval of a minute or more; HOURLY, to specify repeating
- events based on an interval of an hour or more; DAILY, to specify
- repeating events based on an interval of a day or more; WEEKLY, to
- specify repeating events based on an interval of a week or more;
- MONTHLY, to specify repeating events based on an interval of a
- month or more; and YEARLY, to specify repeating events based on an
- interval of a year or more.
-
-
-
-
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-
-
- The INTERVAL rule part contains a positive integer representing at
- which intervals the recurrence rule repeats. The default value is
- "1", meaning every second for a SECONDLY rule, every minute for a
- MINUTELY rule, every hour for an HOURLY rule, every day for a
- DAILY rule, every week for a WEEKLY rule, every month for a
- MONTHLY rule, and every year for a YEARLY rule. For example,
- within a DAILY rule, a value of "8" means every eight days.
-
- The UNTIL rule part defines a DATE or DATE-TIME value that bounds
- the recurrence rule in an inclusive manner. If the value
- specified by UNTIL is synchronized with the specified recurrence,
- this DATE or DATE-TIME becomes the last instance of the
- recurrence. The value of the UNTIL rule part MUST have the same
- value type as the "DTSTART" property. Furthermore, if the
- "DTSTART" property is specified as a date with local time, then
- the UNTIL rule part MUST also be specified as a date with local
- time. If the "DTSTART" property is specified as a date with UTC
- time or a date with local time and time zone reference, then the
- UNTIL rule part MUST be specified as a date with UTC time. In the
- case of the "STANDARD" and "DAYLIGHT" sub-components the UNTIL
- rule part MUST always be specified as a date with UTC time. If
- specified as a DATE-TIME value, then it MUST be specified in a UTC
- time format. If not present, and the COUNT rule part is also not
- present, the "RRULE" is considered to repeat forever.
-
- The COUNT rule part defines the number of occurrences at which to
- range-bound the recurrence. The "DTSTART" property value always
- counts as the first occurrence.
-
- The BYSECOND rule part specifies a COMMA-separated list of seconds
- within a minute. Valid values are 0 to 60. The BYMINUTE rule
- part specifies a COMMA-separated list of minutes within an hour.
- Valid values are 0 to 59. The BYHOUR rule part specifies a COMMA-
- separated list of hours of the day. Valid values are 0 to 23.
- The BYSECOND, BYMINUTE and BYHOUR rule parts MUST NOT be specified
- when the associated "DTSTART" property has a DATE value type.
- These rule parts MUST be ignored in RECUR value that violate the
- above requirement (e.g., generated by applications that pre-date
- this revision of iCalendar).
-
- The BYDAY rule part specifies a COMMA-separated list of days of
- the week; SU indicates Sunday; MO indicates Monday; TU indicates
- Tuesday; WE indicates Wednesday; TH indicates Thursday; FR
- indicates Friday; and SA indicates Saturday.
-
- Each BYDAY value can also be preceded by a positive (+n) or
- negative (-n) integer. If present, this indicates the nth
- occurrence of a specific day within the MONTHLY or YEARLY "RRULE".
-
-
-
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-
-
- For example, within a MONTHLY rule, +1MO (or simply 1MO)
- represents the first Monday within the month, whereas -1MO
- represents the last Monday of the month. The numeric value in a
- BYDAY rule part with the FREQ rule part set to YEARLY corresponds
- to an offset within the month when the BYMONTH rule part is
- present, and corresponds to an offset within the year when the
- BYWEEKNO or BYMONTH rule parts are present. If an integer
- modifier is not present, it means all days of this type within the
- specified frequency. For example, within a MONTHLY rule, MO
- represents all Mondays within the month. The BYDAY rule part MUST
- NOT be specified with a numeric value when the FREQ rule part is
- not set to MONTHLY or YEARLY. Furthermore, the BYDAY rule part
- MUST NOT be specified with a numeric value with the FREQ rule part
- set to YEARLY when the BYWEEKNO rule part is specified.
-
- The BYMONTHDAY rule part specifies a COMMA-separated list of days
- of the month. Valid values are 1 to 31 or -31 to -1. For
- example, -10 represents the tenth to the last day of the month.
- The BYMONTHDAY rule part MUST NOT be specified when the FREQ rule
- part is set to WEEKLY.
-
- The BYYEARDAY rule part specifies a COMMA-separated list of days
- of the year. Valid values are 1 to 366 or -366 to -1. For
- example, -1 represents the last day of the year (December 31st)
- and -306 represents the 306th to the last day of the year (March
- 1st). The BYYEARDAY rule part MUST NOT be specified when the FREQ
- rule part is set to DAILY, WEEKLY, or MONTHLY.
-
- The BYWEEKNO rule part specifies a COMMA-separated list of
- ordinals specifying weeks of the year. Valid values are 1 to 53
- or -53 to -1. This corresponds to weeks according to week
- numbering as defined in [ISO.8601.2004]. A week is defined as a
- seven day period, starting on the day of the week defined to be
- the week start (see WKST). Week number one of the calendar year
- is the first week that contains at least four (4) days in that
- calendar year. This rule part MUST NOT be used when the FREQ rule
- part is set to anything other than YEARLY. For example, 3
- represents the third week of the year.
-
- Note: Assuming a Monday week start, week 53 can only occur when
- Thursday is January 1 or if it is a leap year and Wednesday is
- January 1.
-
- The BYMONTH rule part specifies a COMMA-separated list of months
- of the year. Valid values are 1 to 12.
-
- The WKST rule part specifies the day on which the workweek starts.
- Valid values are MO, TU, WE, TH, FR, SA, and SU. This is
-
-
-
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-
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-
-
- significant when a WEEKLY "RRULE" has an interval greater than 1,
- and a BYDAY rule part is specified. This is also significant when
- in a YEARLY "RRULE" when a BYWEEKNO rule part is specified. The
- default value is MO.
-
- The BYSETPOS rule part specifies a COMMA-separated list of values
- that corresponds to the nth occurrence within the set of
- recurrence instances specified by the rule. BYSETPOS operates on
- a set of recurrence instances in one interval of the recurrence
- rule. For example, in a WEEKLY rule, the interval would be one
- week A set of recurrence instances starts at the beginning of the
- interval defined by the FREQ rule part. Valid values are 1 to 366
- or -366 to -1. It MUST only be used in conjunction with another
- BYxxx rule part. For example "the last work day of the month"
- could be represented as:
-
- FREQ=MONTHLY;BYDAY=MO,TU,WE,TH,FR;BYSETPOS=-1
-
- Each BYSETPOS value can include a positive (+n) or negative (-n)
- integer. If present, this indicates the nth occurrence of the
- specific occurrence within the set of occurrences specified by the
- rule.
-
- Recurrence rules may generate recurrence instances with an invalid
- date (e.g., February 30) or nonexistent local time (e.g., 1:30 AM
- on a day where the local time is moved forward by an hour at 1:00
- AM). Such recurrence instances MUST be ignored and MUST NOT be
- counted as part of the recurrence set.
-
- Information, not contained in the rule, necessary to determine the
- various recurrence instance start time and dates are derived from
- the Start Time ("DTSTART") component attribute. For example,
- "FREQ=YEARLY;BYMONTH=1" doesn't specify a specific day within the
- month or a time. This information would be the same as what is
- specified for "DTSTART".
-
- BYxxx rule parts modify the recurrence in some manner. BYxxx rule
- parts for a period of time that is the same or greater than the
- frequency generally reduce or limit the number of occurrences of
- the recurrence generated. For example, "FREQ=DAILY;BYMONTH=1"
- reduces the number of recurrence instances from all days (if
- BYMONTH rule part is not present) to all days in January. BYxxx
- rule parts for a period of time less than the frequency generally
- increase or expand the number of occurrences of the recurrence.
- For example, "FREQ=YEARLY;BYMONTH=1,2" increases the number of
- days within the yearly recurrence set from 1 (if BYMONTH rule part
- is not present) to 2.
-
-
-
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-
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-
-
- If multiple BYxxx rule parts are specified, then after evaluating
- the specified FREQ and INTERVAL rule parts, the BYxxx rule parts
- are applied to the current set of evaluated occurrences in the
- following order: BYMONTH, BYWEEKNO, BYYEARDAY, BYMONTHDAY, BYDAY,
- BYHOUR, BYMINUTE, BYSECOND and BYSETPOS; then COUNT and UNTIL are
- evaluated.
-
- The table below summarizes the dependency of BYxxx rule part
- expand or limit behavior on the FREQ rule part value.
-
- The term "N/A" means that the corresponding BYxxx rule part MUST
- NOT be used with the corresponding FREQ value.
-
- BYDAY has some special behavior depending on the FREQ value and
- this is described in separate notes below the table.
-
- +----------+--------+--------+-------+-------+------+-------+------+
- | |SECONDLY|MINUTELY|HOURLY |DAILY |WEEKLY|MONTHLY|YEARLY|
- +----------+--------+--------+-------+-------+------+-------+------+
- |BYMONTH |Limit |Limit |Limit |Limit |Limit |Limit |Expand|
- +----------+--------+--------+-------+-------+------+-------+------+
- |BYWEEKNO |N/A |N/A |N/A |N/A |N/A |N/A |Expand|
- +----------+--------+--------+-------+-------+------+-------+------+
- |BYYEARDAY |Limit |Limit |Limit |N/A |N/A |N/A |Expand|
- +----------+--------+--------+-------+-------+------+-------+------+
- |BYMONTHDAY|Limit |Limit |Limit |Limit |N/A |Expand |Expand|
- +----------+--------+--------+-------+-------+------+-------+------+
- |BYDAY |Limit |Limit |Limit |Limit |Expand|Note 1 |Note 2|
- +----------+--------+--------+-------+-------+------+-------+------+
- |BYHOUR |Limit |Limit |Limit |Expand |Expand|Expand |Expand|
- +----------+--------+--------+-------+-------+------+-------+------+
- |BYMINUTE |Limit |Limit |Expand |Expand |Expand|Expand |Expand|
- +----------+--------+--------+-------+-------+------+-------+------+
- |BYSECOND |Limit |Expand |Expand |Expand |Expand|Expand |Expand|
- +----------+--------+--------+-------+-------+------+-------+------+
- |BYSETPOS |Limit |Limit |Limit |Limit |Limit |Limit |Limit |
- +----------+--------+--------+-------+-------+------+-------+------+
-
- Note 1: Limit if BYMONTHDAY is present; otherwise, special expand
- for MONTHLY.
-
- Note 2: Limit if BYYEARDAY or BYMONTHDAY is present; otherwise,
- special expand for WEEKLY if BYWEEKNO present; otherwise,
- special expand for MONTHLY if BYMONTH present; otherwise,
- special expand for YEARLY.
-
-
-
-
-
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-
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-
-
- Here is an example of evaluating multiple BYxxx rule parts.
-
- DTSTART;TZID=America/New_York:19970105T083000
- RRULE:FREQ=YEARLY;INTERVAL=2;BYMONTH=1;BYDAY=SU;BYHOUR=8,9;
- BYMINUTE=30
-
- First, the "INTERVAL=2" would be applied to "FREQ=YEARLY" to
- arrive at "every other year". Then, "BYMONTH=1" would be applied
- to arrive at "every January, every other year". Then, "BYDAY=SU"
- would be applied to arrive at "every Sunday in January, every
- other year". Then, "BYHOUR=8,9" would be applied to arrive at
- "every Sunday in January at 8 AM and 9 AM, every other year".
- Then, "BYMINUTE=30" would be applied to arrive at "every Sunday in
- January at 8:30 AM and 9:30 AM, every other year". Then, lacking
- information from "RRULE", the second is derived from "DTSTART", to
- end up in "every Sunday in January at 8:30:00 AM and 9:30:00 AM,
- every other year". Similarly, if the BYMINUTE, BYHOUR, BYDAY,
- BYMONTHDAY, or BYMONTH rule part were missing, the appropriate
- minute, hour, day, or month would have been retrieved from the
- "DTSTART" property.
-
- If the computed local start time of a recurrence instance does not
- exist, or occurs more than once, for the specified time zone, the
- time of the recurrence instance is interpreted in the same manner
- as an explicit DATE-TIME value describing that date and time, as
- specified in Section 3.3.5.
-
- No additional content value encoding (i.e., BACKSLASH character
- encoding, see Section 3.3.11) is defined for this value type.
-
- Example: The following is a rule that specifies 10 occurrences that
- occur every other day:
-
- FREQ=DAILY;COUNT=10;INTERVAL=2
-
- There are other examples specified in Section 3.8.5.3.
-
-3.3.11. Text
-
- Value Name: TEXT
-
- Purpose: This value type is used to identify values that contain
- human-readable text.
-
- Format Definition: This value type is defined by the following
- notation:
-
-
-
-
-
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-
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-
-
- text = *(TSAFE-CHAR / ":" / DQUOTE / ESCAPED-CHAR)
- ; Folded according to description above
-
- ESCAPED-CHAR = ("\\" / "\;" / "\," / "\N" / "\n")
- ; \\ encodes \, \N or \n encodes newline
- ; \; encodes ;, \, encodes ,
-
- TSAFE-CHAR = WSP / %x21 / %x23-2B / %x2D-39 / %x3C-5B /
- %x5D-7E / NON-US-ASCII
- ; Any character except CONTROLs not needed by the current
- ; character set, DQUOTE, ";", ":", "\", ","
-
- Description: If the property permits, multiple TEXT values are
- specified by a COMMA-separated list of values.
-
- The language in which the text is represented can be controlled by
- the "LANGUAGE" property parameter.
-
- An intentional formatted text line break MUST only be included in
- a "TEXT" property value by representing the line break with the
- character sequence of BACKSLASH, followed by a LATIN SMALL LETTER
- N or a LATIN CAPITAL LETTER N, that is "\n" or "\N".
-
- The "TEXT" property values may also contain special characters
- that are used to signify delimiters, such as a COMMA character for
- lists of values or a SEMICOLON character for structured values.
- In order to support the inclusion of these special characters in
- "TEXT" property values, they MUST be escaped with a BACKSLASH
- character. A BACKSLASH character in a "TEXT" property value MUST
- be escaped with another BACKSLASH character. A COMMA character in
- a "TEXT" property value MUST be escaped with a BACKSLASH
- character. A SEMICOLON character in a "TEXT" property value MUST
- be escaped with a BACKSLASH character. However, a COLON character
- in a "TEXT" property value SHALL NOT be escaped with a BACKSLASH
- character.
-
- Example: A multiple line value of:
-
- Project XYZ Final Review
- Conference Room - 3B
- Come Prepared.
-
- would be represented as:
-
- Project XYZ Final Review\nConference Room - 3B\nCome Prepared.
-
-
-
-
-
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-
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-
-
-3.3.12. Time
-
- Value Name: TIME
-
- Purpose: This value type is used to identify values that contain a
- time of day.
-
- Format Definition: This value type is defined by the following
- notation:
-
- time = time-hour time-minute time-second [time-utc]
-
- time-hour = 2DIGIT ;00-23
- time-minute = 2DIGIT ;00-59
- time-second = 2DIGIT ;00-60
- ;The "60" value is used to account for positive "leap" seconds.
-
- time-utc = "Z"
-
- Description: If the property permits, multiple "time" values are
- specified by a COMMA-separated list of values. No additional
- content value encoding (i.e., BACKSLASH character encoding, see
- Section 3.3.11) is defined for this value type.
-
- The "TIME" value type is used to identify values that contain a
- time of day. The format is based on the [ISO.8601.2004] complete
- representation, basic format for a time of day. The text format
- consists of a two-digit, 24-hour of the day (i.e., values 00-23),
- two-digit minute in the hour (i.e., values 00-59), and two-digit
- seconds in the minute (i.e., values 00-60). The seconds value of
- 60 MUST only be used to account for positive "leap" seconds.
- Fractions of a second are not supported by this format.
-
- In parallel to the "DATE-TIME" definition above, the "TIME" value
- type expresses time values in three forms:
-
- The form of time with UTC offset MUST NOT be used. For example,
- the following is not valid for a time value:
-
- 230000-0800 ;Invalid time format
-
- FORM #1 LOCAL TIME
-
- The local time form is simply a time value that does not contain
- the UTC designator nor does it reference a time zone. For
- example, 11:00 PM:
-
- 230000
-
-
-
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-
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-
-
- Time values of this type are said to be "floating" and are not
- bound to any time zone in particular. They are used to represent
- the same hour, minute, and second value regardless of which time
- zone is currently being observed. For example, an event can be
- defined that indicates that an individual will be busy from 11:00
- AM to 1:00 PM every day, no matter which time zone the person is
- in. In these cases, a local time can be specified. The recipient
- of an iCalendar object with a property value consisting of a local
- time, without any relative time zone information, SHOULD interpret
- the value as being fixed to whatever time zone the "ATTENDEE" is
- in at any given moment. This means that two "Attendees", may
- participate in the same event at different UTC times; floating
- time SHOULD only be used where that is reasonable behavior.
-
- In most cases, a fixed time is desired. To properly communicate a
- fixed time in a property value, either UTC time or local time with
- time zone reference MUST be specified.
-
- The use of local time in a TIME value without the "TZID" property
- parameter is to be interpreted as floating time, regardless of the
- existence of "VTIMEZONE" calendar components in the iCalendar
- object.
-
- FORM #2: UTC TIME
-
- UTC time, or absolute time, is identified by a LATIN CAPITAL
- LETTER Z suffix character, the UTC designator, appended to the
- time value. For example, the following represents 07:00 AM UTC:
-
- 070000Z
-
- The "TZID" property parameter MUST NOT be applied to TIME
- properties whose time values are specified in UTC.
-
- FORM #3: LOCAL TIME AND TIME ZONE REFERENCE
-
- The local time with reference to time zone information form is
- identified by the use the "TZID" property parameter to reference
- the appropriate time zone definition. "TZID" is discussed in
- detail in Section 3.2.19.
-
- Example: The following represents 8:30 AM in New York in winter,
- five hours behind UTC, in each of the three formats:
-
- 083000
- 133000Z
- TZID=America/New_York:083000
-
-
-
-
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-
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-
-
-3.3.13. URI
-
- Value Name: URI
-
- Purpose: This value type is used to identify values that contain a
- uniform resource identifier (URI) type of reference to the
- property value.
-
- Format Definition: This value type is defined by the following
- notation:
-
- uri = <As defined in Section 3 of [RFC3986]>
-
- Description: This value type might be used to reference binary
- information, for values that are large, or otherwise undesirable
- to include directly in the iCalendar object.
-
- Property values with this value type MUST follow the generic URI
- syntax defined in [RFC3986].
-
- When a property parameter value is a URI value type, the URI MUST
- be specified as a quoted-string value.
-
- No additional content value encoding (i.e., BACKSLASH character
- encoding, see Section 3.3.11) is defined for this value type.
-
- Example: The following is a URI for a network file:
-
- http://example.com/my-report.txt
-
-3.3.14. UTC Offset
-
- Value Name: UTC-OFFSET
-
- Purpose: This value type is used to identify properties that contain
- an offset from UTC to local time.
-
- Format Definition: This value type is defined by the following
- notation:
-
- utc-offset = time-numzone
-
- time-numzone = ("+" / "-") time-hour time-minute [time-second]
-
- Description: The PLUS SIGN character MUST be specified for positive
- UTC offsets (i.e., ahead of UTC). The HYPHEN-MINUS character MUST
- be specified for negative UTC offsets (i.e., behind of UTC). The
-
-
-
-
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-
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-
-
- value of "-0000" and "-000000" are not allowed. The time-second,
- if present, MUST NOT be 60; if absent, it defaults to zero.
-
- No additional content value encoding (i.e., BACKSLASH character
- encoding, see Section 3.3.11) is defined for this value type.
-
- Example: The following UTC offsets are given for standard time for
- New York (five hours behind UTC) and Geneva (one hour ahead of
- UTC):
-
- -0500
-
- +0100
-
-3.4. iCalendar Object
-
- The Calendaring and Scheduling Core Object is a collection of
- calendaring and scheduling information. Typically, this information
- will consist of an iCalendar stream with a single iCalendar object.
- However, multiple iCalendar objects can be sequentially grouped
- together in an iCalendar stream. The first line and last line of the
- iCalendar object MUST contain a pair of iCalendar object delimiter
- strings. The syntax for an iCalendar stream is as follows:
-
- icalstream = 1*icalobject
-
- icalobject = "BEGIN" ":" "VCALENDAR" CRLF
- icalbody
- "END" ":" "VCALENDAR" CRLF
-
- The following is a simple example of an iCalendar object:
-
- BEGIN:VCALENDAR
- VERSION:2.0
- PRODID:-//hacksw/handcal//NONSGML v1.0//EN
- BEGIN:VEVENT
- UID:19970610T172345Z-AF23B2@example.com
- DTSTAMP:19970610T172345Z
- DTSTART:19970714T170000Z
- DTEND:19970715T040000Z
- SUMMARY:Bastille Day Party
- END:VEVENT
- END:VCALENDAR
-
-
-
-
-
-
-
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-
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-
-
-3.5. Property
-
- A property is the definition of an individual attribute describing a
- calendar object or a calendar component. A property takes the form
- defined by the "contentline" notation defined in Section 3.1.
-
- The following is an example of a property:
-
- DTSTART:19960415T133000Z
-
- This memo imposes no ordering of properties within an iCalendar
- object.
-
- Property names, parameter names, and enumerated parameter values are
- case-insensitive. For example, the property name "DUE" is the same
- as "due" and "Due", DTSTART;TZID=America/New_York:19980714T120000 is
- the same as DtStart;TzID=America/New_York:19980714T120000.
-
-3.6. Calendar Components
-
- The body of the iCalendar object consists of a sequence of calendar
- properties and one or more calendar components. The calendar
- properties are attributes that apply to the calendar object as a
- whole. The calendar components are collections of properties that
- express a particular calendar semantic. For example, the calendar
- component can specify an event, a to-do, a journal entry, time zone
- information, free/busy time information, or an alarm.
-
- The body of the iCalendar object is defined by the following
- notation:
-
- icalbody = calprops component
-
- calprops = *(
- ;
- ; The following are REQUIRED,
- ; but MUST NOT occur more than once.
- ;
- prodid / version /
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- calscale / method /
- ;
- ; The following are OPTIONAL,
- ; and MAY occur more than once.
- ;
-
-
-
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-
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-
-
- x-prop / iana-prop
- ;
- )
-
- component = 1*(eventc / todoc / journalc / freebusyc /
- timezonec / iana-comp / x-comp)
-
- iana-comp = "BEGIN" ":" iana-token CRLF
- 1*contentline
- "END" ":" iana-token CRLF
-
- x-comp = "BEGIN" ":" x-name CRLF
- 1*contentline
- "END" ":" x-name CRLF
-
- An iCalendar object MUST include the "PRODID" and "VERSION" calendar
- properties. In addition, it MUST include at least one calendar
- component. Special forms of iCalendar objects are possible to
- publish just busy time (i.e., only a "VFREEBUSY" calendar component)
- or time zone (i.e., only a "VTIMEZONE" calendar component)
- information. In addition, a complex iCalendar object that is used to
- capture a complete snapshot of the contents of a calendar is possible
- (e.g., composite of many different calendar components). More
- commonly, an iCalendar object will consist of just a single "VEVENT",
- "VTODO", or "VJOURNAL" calendar component. Applications MUST ignore
- x-comp and iana-comp values they don't recognize. Applications that
- support importing iCalendar objects SHOULD support all of the
- component types defined in this document, and SHOULD NOT silently
- drop any components as that can lead to user data loss.
-
-3.6.1. Event Component
-
- Component Name: VEVENT
-
- Purpose: Provide a grouping of component properties that describe an
- event.
-
- Format Definition: A "VEVENT" calendar component is defined by the
- following notation:
-
- eventc = "BEGIN" ":" "VEVENT" CRLF
- eventprop *alarmc
- "END" ":" "VEVENT" CRLF
-
- eventprop = *(
- ;
- ; The following are REQUIRED,
- ; but MUST NOT occur more than once.
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- ;
- dtstamp / uid /
- ;
- ; The following is REQUIRED if the component
- ; appears in an iCalendar object that doesn't
- ; specify the "METHOD" property; otherwise, it
- ; is OPTIONAL; in any case, it MUST NOT occur
- ; more than once.
- ;
- dtstart /
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- class / created / description / geo /
- last-mod / location / organizer / priority /
- seq / status / summary / transp /
- url / recurid /
- ;
- ; The following is OPTIONAL,
- ; but SHOULD NOT occur more than once.
- ;
- rrule /
- ;
- ; Either 'dtend' or 'duration' MAY appear in
- ; a 'eventprop', but 'dtend' and 'duration'
- ; MUST NOT occur in the same 'eventprop'.
- ;
- dtend / duration /
- ;
- ; The following are OPTIONAL,
- ; and MAY occur more than once.
- ;
- attach / attendee / categories / comment /
- contact / exdate / rstatus / related /
- resources / rdate / x-prop / iana-prop
- ;
- )
-
- Description: A "VEVENT" calendar component is a grouping of
- component properties, possibly including "VALARM" calendar
- components, that represents a scheduled amount of time on a
- calendar. For example, it can be an activity; such as a one-hour
- long, department meeting from 8:00 AM to 9:00 AM, tomorrow.
- Generally, an event will take up time on an individual calendar.
- Hence, the event will appear as an opaque interval in a search for
- busy time. Alternately, the event can have its Time Transparency
-
-
-
-
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-
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-
-
- set to "TRANSPARENT" in order to prevent blocking of the event in
- searches for busy time.
-
- The "VEVENT" is also the calendar component used to specify an
- anniversary or daily reminder within a calendar. These events
- have a DATE value type for the "DTSTART" property instead of the
- default value type of DATE-TIME. If such a "VEVENT" has a "DTEND"
- property, it MUST be specified as a DATE value also. The
- anniversary type of "VEVENT" can span more than one date (i.e.,
- "DTEND" property value is set to a calendar date after the
- "DTSTART" property value). If such a "VEVENT" has a "DURATION"
- property, it MUST be specified as a "dur-day" or "dur-week" value.
-
- The "DTSTART" property for a "VEVENT" specifies the inclusive
- start of the event. For recurring events, it also specifies the
- very first instance in the recurrence set. The "DTEND" property
- for a "VEVENT" calendar component specifies the non-inclusive end
- of the event. For cases where a "VEVENT" calendar component
- specifies a "DTSTART" property with a DATE value type but no
- "DTEND" nor "DURATION" property, the event's duration is taken to
- be one day. For cases where a "VEVENT" calendar component
- specifies a "DTSTART" property with a DATE-TIME value type but no
- "DTEND" property, the event ends on the same calendar date and
- time of day specified by the "DTSTART" property.
-
- The "VEVENT" calendar component cannot be nested within another
- calendar component. However, "VEVENT" calendar components can be
- related to each other or to a "VTODO" or to a "VJOURNAL" calendar
- component with the "RELATED-TO" property.
-
- Example: The following is an example of the "VEVENT" calendar
- component used to represent a meeting that will also be opaque to
- searches for busy time:
-
- BEGIN:VEVENT
- UID:19970901T130000Z-123401@example.com
- DTSTAMP:19970901T130000Z
- DTSTART:19970903T163000Z
- DTEND:19970903T190000Z
- SUMMARY:Annual Employee Review
- CLASS:PRIVATE
- CATEGORIES:BUSINESS,HUMAN RESOURCES
- END:VEVENT
-
- The following is an example of the "VEVENT" calendar component
- used to represent a reminder that will not be opaque, but rather
- transparent, to searches for busy time:
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- BEGIN:VEVENT
- UID:19970901T130000Z-123402@example.com
- DTSTAMP:19970901T130000Z
- DTSTART:19970401T163000Z
- DTEND:19970402T010000Z
- SUMMARY:Laurel is in sensitivity awareness class.
- CLASS:PUBLIC
- CATEGORIES:BUSINESS,HUMAN RESOURCES
- TRANSP:TRANSPARENT
- END:VEVENT
-
- The following is an example of the "VEVENT" calendar component
- used to represent an anniversary that will occur annually:
-
- BEGIN:VEVENT
- UID:19970901T130000Z-123403@example.com
- DTSTAMP:19970901T130000Z
- DTSTART;VALUE=DATE:19971102
- SUMMARY:Our Blissful Anniversary
- TRANSP:TRANSPARENT
- CLASS:CONFIDENTIAL
- CATEGORIES:ANNIVERSARY,PERSONAL,SPECIAL OCCASION
- RRULE:FREQ=YEARLY
- END:VEVENT
-
- The following is an example of the "VEVENT" calendar component
- used to represent a multi-day event scheduled from June 28th, 2007
- to July 8th, 2007 inclusively. Note that the "DTEND" property is
- set to July 9th, 2007, since the "DTEND" property specifies the
- non-inclusive end of the event.
-
- BEGIN:VEVENT
- UID:20070423T123432Z-541111@example.com
- DTSTAMP:20070423T123432Z
- DTSTART;VALUE=DATE:20070628
- DTEND;VALUE=DATE:20070709
- SUMMARY:Festival International de Jazz de Montreal
- TRANSP:TRANSPARENT
- END:VEVENT
-
-3.6.2. To-Do Component
-
- Component Name: VTODO
-
- Purpose: Provide a grouping of calendar properties that describe a
- to-do.
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Format Definition: A "VTODO" calendar component is defined by the
- following notation:
-
- todoc = "BEGIN" ":" "VTODO" CRLF
- todoprop *alarmc
- "END" ":" "VTODO" CRLF
-
- todoprop = *(
- ;
- ; The following are REQUIRED,
- ; but MUST NOT occur more than once.
- ;
- dtstamp / uid /
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- class / completed / created / description /
- dtstart / geo / last-mod / location / organizer /
- percent / priority / recurid / seq / status /
- summary / url /
- ;
- ; The following is OPTIONAL,
- ; but SHOULD NOT occur more than once.
- ;
- rrule /
- ;
- ; Either 'due' or 'duration' MAY appear in
- ; a 'todoprop', but 'due' and 'duration'
- ; MUST NOT occur in the same 'todoprop'.
- ; If 'duration' appear in a 'todoprop',
- ; then 'dtstart' MUST also appear in
- ; the same 'todoprop'.
- ;
- due / duration /
- ;
- ; The following are OPTIONAL,
- ; and MAY occur more than once.
- ;
- attach / attendee / categories / comment / contact /
- exdate / rstatus / related / resources /
- rdate / x-prop / iana-prop
- ;
- )
-
- Description: A "VTODO" calendar component is a grouping of component
- properties and possibly "VALARM" calendar components that
- represent an action-item or assignment. For example, it can be
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- used to represent an item of work assigned to an individual; such
- as "turn in travel expense today".
-
- The "VTODO" calendar component cannot be nested within another
- calendar component. However, "VTODO" calendar components can be
- related to each other or to a "VEVENT" or to a "VJOURNAL" calendar
- component with the "RELATED-TO" property.
-
- A "VTODO" calendar component without the "DTSTART" and "DUE" (or
- "DURATION") properties specifies a to-do that will be associated
- with each successive calendar date, until it is completed.
-
- Examples: The following is an example of a "VTODO" calendar
- component that needs to be completed before May 1st, 2007. On
- midnight May 1st, 2007 this to-do would be considered overdue.
-
- BEGIN:VTODO
- UID:20070313T123432Z-456553@example.com
- DTSTAMP:20070313T123432Z
- DUE;VALUE=DATE:20070501
- SUMMARY:Submit Quebec Income Tax Return for 2006
- CLASS:CONFIDENTIAL
- CATEGORIES:FAMILY,FINANCE
- STATUS:NEEDS-ACTION
- END:VTODO
-
- The following is an example of a "VTODO" calendar component that
- was due before 1:00 P.M. UTC on July 9th, 2007 and was completed
- on July 7th, 2007 at 10:00 A.M. UTC.
-
- BEGIN:VTODO
- UID:20070514T103211Z-123404@example.com
- DTSTAMP:20070514T103211Z
- DTSTART:20070514T110000Z
- DUE:20070709T130000Z
- COMPLETED:20070707T100000Z
- SUMMARY:Submit Revised Internet-Draft
- PRIORITY:1
- STATUS:NEEDS-ACTION
- END:VTODO
-
-3.6.3. Journal Component
-
- Component Name: VJOURNAL
-
- Purpose: Provide a grouping of component properties that describe a
- journal entry.
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Format Definition: A "VJOURNAL" calendar component is defined by the
- following notation:
-
- journalc = "BEGIN" ":" "VJOURNAL" CRLF
- jourprop
- "END" ":" "VJOURNAL" CRLF
-
- jourprop = *(
- ;
- ; The following are REQUIRED,
- ; but MUST NOT occur more than once.
- ;
- dtstamp / uid /
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- class / created / dtstart /
- last-mod / organizer / recurid / seq /
- status / summary / url /
- ;
- ; The following is OPTIONAL,
- ; but SHOULD NOT occur more than once.
- ;
- rrule /
- ;
- ; The following are OPTIONAL,
- ; and MAY occur more than once.
- ;
- attach / attendee / categories / comment /
- contact / description / exdate / related / rdate /
- rstatus / x-prop / iana-prop
- ;
- )
-
- Description: A "VJOURNAL" calendar component is a grouping of
- component properties that represent one or more descriptive text
- notes associated with a particular calendar date. The "DTSTART"
- property is used to specify the calendar date with which the
- journal entry is associated. Generally, it will have a DATE value
- data type, but it can also be used to specify a DATE-TIME value
- data type. Examples of a journal entry include a daily record of
- a legislative body or a journal entry of individual telephone
- contacts for the day or an ordered list of accomplishments for the
- day. The "VJOURNAL" calendar component can also be used to
- associate a document with a calendar date.
-
-
-
-
-
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-
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-
-
- The "VJOURNAL" calendar component does not take up time on a
- calendar. Hence, it does not play a role in free or busy time
- searches -- it is as though it has a time transparency value of
- TRANSPARENT. It is transparent to any such searches.
-
- The "VJOURNAL" calendar component cannot be nested within another
- calendar component. However, "VJOURNAL" calendar components can
- be related to each other or to a "VEVENT" or to a "VTODO" calendar
- component, with the "RELATED-TO" property.
-
- Example: The following is an example of the "VJOURNAL" calendar
- component:
-
- BEGIN:VJOURNAL
- UID:19970901T130000Z-123405@example.com
- DTSTAMP:19970901T130000Z
- DTSTART;VALUE=DATE:19970317
- SUMMARY:Staff meeting minutes
- DESCRIPTION:1. Staff meeting: Participants include Joe\,
- Lisa\, and Bob. Aurora project plans were reviewed.
- There is currently no budget reserves for this project.
- Lisa will escalate to management. Next meeting on Tuesday.\n
- 2. Telephone Conference: ABC Corp. sales representative
- called to discuss new printer. Promised to get us a demo by
- Friday.\n3. Henry Miller (Handsoff Insurance): Car was
- totaled by tree. Is looking into a loaner car. 555-2323
- (tel).
- END:VJOURNAL
-
-3.6.4. Free/Busy Component
-
- Component Name: VFREEBUSY
-
- Purpose: Provide a grouping of component properties that describe
- either a request for free/busy time, describe a response to a
- request for free/busy time, or describe a published set of busy
- time.
-
- Format Definition: A "VFREEBUSY" calendar component is defined by
- the following notation:
-
- freebusyc = "BEGIN" ":" "VFREEBUSY" CRLF
- fbprop
- "END" ":" "VFREEBUSY" CRLF
-
- fbprop = *(
- ;
- ; The following are REQUIRED,
-
-
-
-Desruisseaux Standards Track [Page 59]
-
-RFC 5545 iCalendar September 2009
-
-
- ; but MUST NOT occur more than once.
- ;
- dtstamp / uid /
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- contact / dtstart / dtend /
- organizer / url /
- ;
- ; The following are OPTIONAL,
- ; and MAY occur more than once.
- ;
- attendee / comment / freebusy / rstatus / x-prop /
- iana-prop
- ;
- )
-
- Description: A "VFREEBUSY" calendar component is a grouping of
- component properties that represents either a request for free or
- busy time information, a reply to a request for free or busy time
- information, or a published set of busy time information.
-
- When used to request free/busy time information, the "ATTENDEE"
- property specifies the calendar users whose free/busy time is
- being requested; the "ORGANIZER" property specifies the calendar
- user who is requesting the free/busy time; the "DTSTART" and
- "DTEND" properties specify the window of time for which the free/
- busy time is being requested; the "UID" and "DTSTAMP" properties
- are specified to assist in proper sequencing of multiple free/busy
- time requests.
-
- When used to reply to a request for free/busy time, the "ATTENDEE"
- property specifies the calendar user responding to the free/busy
- time request; the "ORGANIZER" property specifies the calendar user
- that originally requested the free/busy time; the "FREEBUSY"
- property specifies the free/busy time information (if it exists);
- and the "UID" and "DTSTAMP" properties are specified to assist in
- proper sequencing of multiple free/busy time replies.
-
- When used to publish busy time, the "ORGANIZER" property specifies
- the calendar user associated with the published busy time; the
- "DTSTART" and "DTEND" properties specify an inclusive time window
- that surrounds the busy time information; the "FREEBUSY" property
- specifies the published busy time information; and the "DTSTAMP"
- property specifies the DATE-TIME that iCalendar object was
- created.
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- The "VFREEBUSY" calendar component cannot be nested within another
- calendar component. Multiple "VFREEBUSY" calendar components can
- be specified within an iCalendar object. This permits the
- grouping of free/busy information into logical collections, such
- as monthly groups of busy time information.
-
- The "VFREEBUSY" calendar component is intended for use in
- iCalendar object methods involving requests for free time,
- requests for busy time, requests for both free and busy, and the
- associated replies.
-
- Free/Busy information is represented with the "FREEBUSY" property.
- This property provides a terse representation of time periods.
- One or more "FREEBUSY" properties can be specified in the
- "VFREEBUSY" calendar component.
-
- When present in a "VFREEBUSY" calendar component, the "DTSTART"
- and "DTEND" properties SHOULD be specified prior to any "FREEBUSY"
- properties.
-
- The recurrence properties ("RRULE", "RDATE", "EXDATE") are not
- permitted within a "VFREEBUSY" calendar component. Any recurring
- events are resolved into their individual busy time periods using
- the "FREEBUSY" property.
-
- Example: The following is an example of a "VFREEBUSY" calendar
- component used to request free or busy time information:
-
- BEGIN:VFREEBUSY
- UID:19970901T082949Z-FA43EF@example.com
- ORGANIZER:mailto:jane_doe@example.com
- ATTENDEE:mailto:john_public@example.com
- DTSTART:19971015T050000Z
- DTEND:19971016T050000Z
- DTSTAMP:19970901T083000Z
- END:VFREEBUSY
-
-
-
-
-
-
-
-
-
-
-
-
-
-
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-
-
- The following is an example of a "VFREEBUSY" calendar component
- used to reply to the request with busy time information:
-
- BEGIN:VFREEBUSY
- UID:19970901T095957Z-76A912@example.com
- ORGANIZER:mailto:jane_doe@example.com
- ATTENDEE:mailto:john_public@example.com
- DTSTAMP:19970901T100000Z
- FREEBUSY:19971015T050000Z/PT8H30M,
- 19971015T160000Z/PT5H30M,19971015T223000Z/PT6H30M
- URL:http://example.com/pub/busy/jpublic-01.ifb
- COMMENT:This iCalendar file contains busy time information for
- the next three months.
- END:VFREEBUSY
-
- The following is an example of a "VFREEBUSY" calendar component
- used to publish busy time information:
-
- BEGIN:VFREEBUSY
- UID:19970901T115957Z-76A912@example.com
- DTSTAMP:19970901T120000Z
- ORGANIZER:jsmith@example.com
- DTSTART:19980313T141711Z
- DTEND:19980410T141711Z
- FREEBUSY:19980314T233000Z/19980315T003000Z
- FREEBUSY:19980316T153000Z/19980316T163000Z
- FREEBUSY:19980318T030000Z/19980318T040000Z
- URL:http://www.example.com/calendar/busytime/jsmith.ifb
- END:VFREEBUSY
-
-3.6.5. Time Zone Component
-
- Component Name: VTIMEZONE
-
- Purpose: Provide a grouping of component properties that defines a
- time zone.
-
- Format Definition: A "VTIMEZONE" calendar component is defined by
- the following notation:
-
- timezonec = "BEGIN" ":" "VTIMEZONE" CRLF
- *(
- ;
- ; 'tzid' is REQUIRED, but MUST NOT occur more
- ; than once.
- ;
- tzid /
- ;
-
-
-
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-
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-
-
- ; 'last-mod' and 'tzurl' are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- last-mod / tzurl /
- ;
- ; One of 'standardc' or 'daylightc' MUST occur
- ; and each MAY occur more than once.
- ;
- standardc / daylightc /
- ;
- ; The following are OPTIONAL,
- ; and MAY occur more than once.
- ;
- x-prop / iana-prop
- ;
- )
- "END" ":" "VTIMEZONE" CRLF
-
- standardc = "BEGIN" ":" "STANDARD" CRLF
- tzprop
- "END" ":" "STANDARD" CRLF
-
- daylightc = "BEGIN" ":" "DAYLIGHT" CRLF
- tzprop
- "END" ":" "DAYLIGHT" CRLF
-
- tzprop = *(
- ;
- ; The following are REQUIRED,
- ; but MUST NOT occur more than once.
- ;
- dtstart / tzoffsetto / tzoffsetfrom /
- ;
- ; The following is OPTIONAL,
- ; but SHOULD NOT occur more than once.
- ;
- rrule /
- ;
- ; The following are OPTIONAL,
- ; and MAY occur more than once.
- ;
- comment / rdate / tzname / x-prop / iana-prop
- ;
- )
-
- Description: A time zone is unambiguously defined by the set of time
- measurement rules determined by the governing body for a given
- geographic area. These rules describe, at a minimum, the base
-
-
-
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-
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-
-
- offset from UTC for the time zone, often referred to as the
- Standard Time offset. Many locations adjust their Standard Time
- forward or backward by one hour, in order to accommodate seasonal
- changes in number of daylight hours, often referred to as Daylight
- Saving Time. Some locations adjust their time by a fraction of an
- hour. Standard Time is also known as Winter Time. Daylight
- Saving Time is also known as Advanced Time, Summer Time, or Legal
- Time in certain countries. The following table shows the changes
- in time zone rules in effect for New York City starting from 1967.
- Each line represents a description or rule for a particular
- observance.
-
- Effective Observance Rule
-
- +-----------+--------------------------+--------+--------------+
- | Date | (Date-Time) | Offset | Abbreviation |
- +-----------+--------------------------+--------+--------------+
- | 1967-1973 | last Sun in Apr, 02:00 | -0400 | EDT |
- | | | | |
- | 1967-2006 | last Sun in Oct, 02:00 | -0500 | EST |
- | | | | |
- | 1974-1974 | Jan 6, 02:00 | -0400 | EDT |
- | | | | |
- | 1975-1975 | Feb 23, 02:00 | -0400 | EDT |
- | | | | |
- | 1976-1986 | last Sun in Apr, 02:00 | -0400 | EDT |
- | | | | |
- | 1987-2006 | first Sun in Apr, 02:00 | -0400 | EDT |
- | | | | |
- | 2007-* | second Sun in Mar, 02:00 | -0400 | EDT |
- | | | | |
- | 2007-* | first Sun in Nov, 02:00 | -0500 | EST |
- +-----------+--------------------------+--------+--------------+
-
- Note: The specification of a global time zone registry is not
- addressed by this document and is left for future study.
- However, implementers may find the TZ database [TZDB] a useful
- reference. It is an informal, public-domain collection of time
- zone information, which is currently being maintained by
- volunteer Internet participants, and is used in several
- operating systems. This database contains current and
- historical time zone information for a wide variety of
- locations around the globe; it provides a time zone identifier
- for every unique time zone rule set in actual use since 1970,
- with historical data going back to the introduction of standard
- time.
-
-
-
-
-
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-
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-
-
- Interoperability between two calendaring and scheduling
- applications, especially for recurring events, to-dos or journal
- entries, is dependent on the ability to capture and convey date
- and time information in an unambiguous format. The specification
- of current time zone information is integral to this behavior.
-
- If present, the "VTIMEZONE" calendar component defines the set of
- Standard Time and Daylight Saving Time observances (or rules) for
- a particular time zone for a given interval of time. The
- "VTIMEZONE" calendar component cannot be nested within other
- calendar components. Multiple "VTIMEZONE" calendar components can
- exist in an iCalendar object. In this situation, each "VTIMEZONE"
- MUST represent a unique time zone definition. This is necessary
- for some classes of events, such as airline flights, that start in
- one time zone and end in another.
-
- The "VTIMEZONE" calendar component MUST include the "TZID"
- property and at least one definition of a "STANDARD" or "DAYLIGHT"
- sub-component. The "STANDARD" or "DAYLIGHT" sub-component MUST
- include the "DTSTART", "TZOFFSETFROM", and "TZOFFSETTO"
- properties.
-
- An individual "VTIMEZONE" calendar component MUST be specified for
- each unique "TZID" parameter value specified in the iCalendar
- object. In addition, a "VTIMEZONE" calendar component, referred
- to by a recurring calendar component, MUST provide valid time zone
- information for all recurrence instances.
-
- Each "VTIMEZONE" calendar component consists of a collection of
- one or more sub-components that describe the rule for a particular
- observance (either a Standard Time or a Daylight Saving Time
- observance). The "STANDARD" sub-component consists of a
- collection of properties that describe Standard Time. The
- "DAYLIGHT" sub-component consists of a collection of properties
- that describe Daylight Saving Time. In general, this collection
- of properties consists of:
-
- * the first onset DATE-TIME for the observance;
-
- * the last onset DATE-TIME for the observance, if a last onset is
- known;
-
- * the offset to be applied for the observance;
-
- * a rule that describes the day and time when the observance
- takes effect;
-
- * an optional name for the observance.
-
-
-
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-
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-
-
- For a given time zone, there may be multiple unique definitions of
- the observances over a period of time. Each observance is
- described using either a "STANDARD" or "DAYLIGHT" sub-component.
- The collection of these sub-components is used to describe the
- time zone for a given period of time. The offset to apply at any
- given time is found by locating the observance that has the last
- onset date and time before the time in question, and using the
- offset value from that observance.
-
- The top-level properties in a "VTIMEZONE" calendar component are:
-
- The mandatory "TZID" property is a text value that uniquely
- identifies the "VTIMEZONE" calendar component within the scope of
- an iCalendar object.
-
- The optional "LAST-MODIFIED" property is a UTC value that
- specifies the date and time that this time zone definition was
- last updated.
-
- The optional "TZURL" property is a url value that points to a
- published "VTIMEZONE" definition. "TZURL" SHOULD refer to a
- resource that is accessible by anyone who might need to interpret
- the object. This SHOULD NOT normally be a "file" URL or other URL
- that is not widely accessible.
-
- The collection of properties that are used to define the
- "STANDARD" and "DAYLIGHT" sub-components include:
-
- The mandatory "DTSTART" property gives the effective onset date
- and local time for the time zone sub-component definition.
- "DTSTART" in this usage MUST be specified as a date with a local
- time value.
-
- The mandatory "TZOFFSETFROM" property gives the UTC offset that is
- in use when the onset of this time zone observance begins.
- "TZOFFSETFROM" is combined with "DTSTART" to define the effective
- onset for the time zone sub-component definition. For example,
- the following represents the time at which the observance of
- Standard Time took effect in Fall 1967 for New York City:
-
- DTSTART:19671029T020000
-
- TZOFFSETFROM:-0400
-
- The mandatory "TZOFFSETTO" property gives the UTC offset for the
- time zone sub-component (Standard Time or Daylight Saving Time)
- when this observance is in use.
-
-
-
-
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-
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-
-
- The optional "TZNAME" property is the customary name for the time
- zone. This could be used for displaying dates.
-
- The onset DATE-TIME values for the observance defined by the time
- zone sub-component is defined by the "DTSTART", "RRULE", and
- "RDATE" properties.
-
- The "RRULE" property defines the recurrence rule for the onset of
- the observance defined by this time zone sub-component. Some
- specific requirements for the usage of "RRULE" for this purpose
- include:
-
- * If observance is known to have an effective end date, the
- "UNTIL" recurrence rule parameter MUST be used to specify the
- last valid onset of this observance (i.e., the UNTIL DATE-TIME
- will be equal to the last instance generated by the recurrence
- pattern). It MUST be specified in UTC time.
-
- * The "DTSTART" and the "TZOFFSETFROM" properties MUST be used
- when generating the onset DATE-TIME values (instances) from the
- "RRULE".
-
- The "RDATE" property can also be used to define the onset of the
- observance by giving the individual onset date and times. "RDATE"
- in this usage MUST be specified as a date with local time value,
- relative to the UTC offset specified in the "TZOFFSETFROM"
- property.
-
- The optional "COMMENT" property is also allowed for descriptive
- explanatory text.
-
- Example: The following are examples of the "VTIMEZONE" calendar
- component:
-
- This is an example showing all the time zone rules for New York
- City since April 30, 1967 at 03:00:00 EDT.
-
- BEGIN:VTIMEZONE
- TZID:America/New_York
- LAST-MODIFIED:20050809T050000Z
- BEGIN:DAYLIGHT
- DTSTART:19670430T020000
- RRULE:FREQ=YEARLY;BYMONTH=4;BYDAY=-1SU;UNTIL=19730429T070000Z
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
- TZNAME:EDT
- END:DAYLIGHT
- BEGIN:STANDARD
-
-
-
-Desruisseaux Standards Track [Page 67]
-
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-
-
- DTSTART:19671029T020000
- RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU;UNTIL=20061029T060000Z
- TZOFFSETFROM:-0400
- TZOFFSETTO:-0500
- TZNAME:EST
- END:STANDARD
- BEGIN:DAYLIGHT
- DTSTART:19740106T020000
- RDATE:19750223T020000
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
- TZNAME:EDT
- END:DAYLIGHT
- BEGIN:DAYLIGHT
- DTSTART:19760425T020000
- RRULE:FREQ=YEARLY;BYMONTH=4;BYDAY=-1SU;UNTIL=19860427T070000Z
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
- TZNAME:EDT
- END:DAYLIGHT
- BEGIN:DAYLIGHT
- DTSTART:19870405T020000
- RRULE:FREQ=YEARLY;BYMONTH=4;BYDAY=1SU;UNTIL=20060402T070000Z
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
- TZNAME:EDT
- END:DAYLIGHT
- BEGIN:DAYLIGHT
- DTSTART:20070311T020000
- RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
- TZNAME:EDT
- END:DAYLIGHT
- BEGIN:STANDARD
- DTSTART:20071104T020000
- RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU
- TZOFFSETFROM:-0400
- TZOFFSETTO:-0500
- TZNAME:EST
- END:STANDARD
- END:VTIMEZONE
-
- This is an example showing time zone information for New York City
- using only the "DTSTART" property. Note that this is only
- suitable for a recurring event that starts on or later than March
- 11, 2007 at 03:00:00 EDT (i.e., the earliest effective transition
- date and time) and ends no later than March 9, 2008 at 01:59:59
-
-
-
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-
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-
-
- EST (i.e., latest valid date and time for EST in this scenario).
- For example, this can be used for a recurring event that occurs
- every Friday, 8:00 A.M.-9:00 A.M., starting June 1, 2007, ending
- December 31, 2007,
-
- BEGIN:VTIMEZONE
- TZID:America/New_York
- LAST-MODIFIED:20050809T050000Z
- BEGIN:STANDARD
- DTSTART:20071104T020000
- TZOFFSETFROM:-0400
- TZOFFSETTO:-0500
- TZNAME:EST
- END:STANDARD
- BEGIN:DAYLIGHT
- DTSTART:20070311T020000
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
- TZNAME:EDT
- END:DAYLIGHT
- END:VTIMEZONE
-
- This is a simple example showing the current time zone rules for
- New York City using a "RRULE" recurrence pattern. Note that there
- is no effective end date to either of the Standard Time or
- Daylight Time rules. This information would be valid for a
- recurring event starting today and continuing indefinitely.
-
- BEGIN:VTIMEZONE
- TZID:America/New_York
- LAST-MODIFIED:20050809T050000Z
- TZURL:http://zones.example.com/tz/America-New_York.ics
- BEGIN:STANDARD
- DTSTART:20071104T020000
- RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU
- TZOFFSETFROM:-0400
- TZOFFSETTO:-0500
- TZNAME:EST
- END:STANDARD
- BEGIN:DAYLIGHT
- DTSTART:20070311T020000
- RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
- TZNAME:EDT
- END:DAYLIGHT
- END:VTIMEZONE
-
-
-
-
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-
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-
-
- This is an example showing a set of rules for a fictitious time
- zone where the Daylight Time rule has an effective end date (i.e.,
- after that date, Daylight Time is no longer observed).
-
- BEGIN:VTIMEZONE
- TZID:Fictitious
- LAST-MODIFIED:19870101T000000Z
- BEGIN:STANDARD
- DTSTART:19671029T020000
- RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
- TZOFFSETFROM:-0400
- TZOFFSETTO:-0500
- TZNAME:EST
- END:STANDARD
- BEGIN:DAYLIGHT
- DTSTART:19870405T020000
- RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4;UNTIL=19980404T070000Z
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
- TZNAME:EDT
- END:DAYLIGHT
- END:VTIMEZONE
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
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-
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-
-
- This is an example showing a set of rules for a fictitious time
- zone where the first Daylight Time rule has an effective end date.
- There is a second Daylight Time rule that picks up where the other
- left off.
-
- BEGIN:VTIMEZONE
- TZID:Fictitious
- LAST-MODIFIED:19870101T000000Z
- BEGIN:STANDARD
- DTSTART:19671029T020000
- RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
- TZOFFSETFROM:-0400
- TZOFFSETTO:-0500
- TZNAME:EST
- END:STANDARD
- BEGIN:DAYLIGHT
- DTSTART:19870405T020000
- RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4;UNTIL=19980404T070000Z
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
- TZNAME:EDT
- END:DAYLIGHT
- BEGIN:DAYLIGHT
- DTSTART:19990424T020000
- RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=4
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
- TZNAME:EDT
- END:DAYLIGHT
- END:VTIMEZONE
-
-3.6.6. Alarm Component
-
- Component Name: VALARM
-
- Purpose: Provide a grouping of component properties that define an
- alarm.
-
- Format Definition: A "VALARM" calendar component is defined by the
- following notation:
-
- alarmc = "BEGIN" ":" "VALARM" CRLF
- (audioprop / dispprop / emailprop)
- "END" ":" "VALARM" CRLF
-
- audioprop = *(
- ;
- ; 'action' and 'trigger' are both REQUIRED,
-
-
-
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-
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-
-
- ; but MUST NOT occur more than once.
- ;
- action / trigger /
- ;
- ; 'duration' and 'repeat' are both OPTIONAL,
- ; and MUST NOT occur more than once each;
- ; but if one occurs, so MUST the other.
- ;
- duration / repeat /
- ;
- ; The following is OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- attach /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- x-prop / iana-prop
- ;
- )
-
- dispprop = *(
- ;
- ; The following are REQUIRED,
- ; but MUST NOT occur more than once.
- ;
- action / description / trigger /
- ;
- ; 'duration' and 'repeat' are both OPTIONAL,
- ; and MUST NOT occur more than once each;
- ; but if one occurs, so MUST the other.
- ;
- duration / repeat /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- x-prop / iana-prop
- ;
- )
-
- emailprop = *(
- ;
- ; The following are all REQUIRED,
- ; but MUST NOT occur more than once.
- ;
- action / description / trigger / summary /
-
-
-
-Desruisseaux Standards Track [Page 72]
-
-RFC 5545 iCalendar September 2009
-
-
- ;
- ; The following is REQUIRED,
- ; and MAY occur more than once.
- ;
- attendee /
- ;
- ; 'duration' and 'repeat' are both OPTIONAL,
- ; and MUST NOT occur more than once each;
- ; but if one occurs, so MUST the other.
- ;
- duration / repeat /
- ;
- ; The following are OPTIONAL,
- ; and MAY occur more than once.
- ;
- attach / x-prop / iana-prop
- ;
- )
-
- Description: A "VALARM" calendar component is a grouping of
- component properties that is a reminder or alarm for an event or a
- to-do. For example, it may be used to define a reminder for a
- pending event or an overdue to-do.
-
- The "VALARM" calendar component MUST include the "ACTION" and
- "TRIGGER" properties. The "ACTION" property further constrains
- the "VALARM" calendar component in the following ways:
-
- When the action is "AUDIO", the alarm can also include one and
- only one "ATTACH" property, which MUST point to a sound resource,
- which is rendered when the alarm is triggered.
-
- When the action is "DISPLAY", the alarm MUST also include a
- "DESCRIPTION" property, which contains the text to be displayed
- when the alarm is triggered.
-
- When the action is "EMAIL", the alarm MUST include a "DESCRIPTION"
- property, which contains the text to be used as the message body,
- a "SUMMARY" property, which contains the text to be used as the
- message subject, and one or more "ATTENDEE" properties, which
- contain the email address of attendees to receive the message. It
- can also include one or more "ATTACH" properties, which are
- intended to be sent as message attachments. When the alarm is
- triggered, the email message is sent.
-
- The "VALARM" calendar component MUST only appear within either a
- "VEVENT" or "VTODO" calendar component. "VALARM" calendar
- components cannot be nested. Multiple mutually independent
-
-
-
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-
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-
-
- "VALARM" calendar components can be specified for a single
- "VEVENT" or "VTODO" calendar component.
-
- The "TRIGGER" property specifies when the alarm will be triggered.
- The "TRIGGER" property specifies a duration prior to the start of
- an event or a to-do. The "TRIGGER" edge may be explicitly set to
- be relative to the "START" or "END" of the event or to-do with the
- "RELATED" parameter of the "TRIGGER" property. The "TRIGGER"
- property value type can alternatively be set to an absolute
- calendar date with UTC time.
-
- In an alarm set to trigger on the "START" of an event or to-do,
- the "DTSTART" property MUST be present in the associated event or
- to-do. In an alarm in a "VEVENT" calendar component set to
- trigger on the "END" of the event, either the "DTEND" property
- MUST be present, or the "DTSTART" and "DURATION" properties MUST
- both be present. In an alarm in a "VTODO" calendar component set
- to trigger on the "END" of the to-do, either the "DUE" property
- MUST be present, or the "DTSTART" and "DURATION" properties MUST
- both be present.
-
- The alarm can be defined such that it triggers repeatedly. A
- definition of an alarm with a repeating trigger MUST include both
- the "DURATION" and "REPEAT" properties. The "DURATION" property
- specifies the delay period, after which the alarm will repeat.
- The "REPEAT" property specifies the number of additional
- repetitions that the alarm will be triggered. This repetition
- count is in addition to the initial triggering of the alarm. Both
- of these properties MUST be present in order to specify a
- repeating alarm. If one of these two properties is absent, then
- the alarm will not repeat beyond the initial trigger.
-
- The "ACTION" property is used within the "VALARM" calendar
- component to specify the type of action invoked when the alarm is
- triggered. The "VALARM" properties provide enough information for
- a specific action to be invoked. It is typically the
- responsibility of a "Calendar User Agent" (CUA) to deliver the
- alarm in the specified fashion. An "ACTION" property value of
- AUDIO specifies an alarm that causes a sound to be played to alert
- the user; DISPLAY specifies an alarm that causes a text message to
- be displayed to the user; and EMAIL specifies an alarm that causes
- an electronic email message to be delivered to one or more email
- addresses.
-
- In an AUDIO alarm, if the optional "ATTACH" property is included,
- it MUST specify an audio sound resource. The intention is that
- the sound will be played as the alarm effect. If an "ATTACH"
- property is specified that does not refer to a sound resource, or
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- if the specified sound resource cannot be rendered (because its
- format is unsupported, or because it cannot be retrieved), then
- the CUA or other entity responsible for playing the sound may
- choose a fallback action, such as playing a built-in default
- sound, or playing no sound at all.
-
- In a DISPLAY alarm, the intended alarm effect is for the text
- value of the "DESCRIPTION" property to be displayed to the user.
-
- In an EMAIL alarm, the intended alarm effect is for an email
- message to be composed and delivered to all the addresses
- specified by the "ATTENDEE" properties in the "VALARM" calendar
- component. The "DESCRIPTION" property of the "VALARM" calendar
- component MUST be used as the body text of the message, and the
- "SUMMARY" property MUST be used as the subject text. Any "ATTACH"
- properties in the "VALARM" calendar component SHOULD be sent as
- attachments to the message.
-
- Note: Implementations should carefully consider whether they
- accept alarm components from untrusted sources, e.g., when
- importing calendar objects from external sources. One
- reasonable policy is to always ignore alarm components that the
- calendar user has not set herself, or at least ask for
- confirmation in such a case.
-
- Example: The following example is for a "VALARM" calendar component
- that specifies an audio alarm that will sound at a precise time
- and repeat 4 more times at 15-minute intervals:
-
- BEGIN:VALARM
- TRIGGER;VALUE=DATE-TIME:19970317T133000Z
- REPEAT:4
- DURATION:PT15M
- ACTION:AUDIO
- ATTACH;FMTTYPE=audio/basic:ftp://example.com/pub/
- sounds/bell-01.aud
- END:VALARM
-
- The following example is for a "VALARM" calendar component that
- specifies a display alarm that will trigger 30 minutes before the
- scheduled start of the event or of the to-do it is associated with
- and will repeat 2 more times at 15-minute intervals:
-
-
-
-
-
-
-
-
-
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-
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-
-
- BEGIN:VALARM
- TRIGGER:-PT30M
- REPEAT:2
- DURATION:PT15M
- ACTION:DISPLAY
- DESCRIPTION:Breakfast meeting with executive\n
- team at 8:30 AM EST.
- END:VALARM
-
- The following example is for a "VALARM" calendar component that
- specifies an email alarm that will trigger 2 days before the
- scheduled due DATE-TIME of a to-do with which it is associated.
- It does not repeat. The email has a subject, body, and attachment
- link.
-
- BEGIN:VALARM
- TRIGGER;RELATED=END:-P2D
- ACTION:EMAIL
- ATTENDEE:mailto:john_doe@example.com
- SUMMARY:*** REMINDER: SEND AGENDA FOR WEEKLY STAFF MEETING ***
- DESCRIPTION:A draft agenda needs to be sent out to the attendees
- to the weekly managers meeting (MGR-LIST). Attached is a
- pointer the document template for the agenda file.
- ATTACH;FMTTYPE=application/msword:http://example.com/
- templates/agenda.doc
- END:VALARM
-
-3.7. Calendar Properties
-
- The Calendar Properties are attributes that apply to the iCalendar
- object, as a whole. These properties do not appear within a calendar
- component. They SHOULD be specified after the "BEGIN:VCALENDAR"
- delimiter string and prior to any calendar component.
-
-3.7.1. Calendar Scale
-
- Property Name: CALSCALE
-
- Purpose: This property defines the calendar scale used for the
- calendar information specified in the iCalendar object.
-
- Value Type: TEXT
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified once in an iCalendar
- object. The default value is "GREGORIAN".
-
-
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-
-
- Description: This memo is based on the Gregorian calendar scale.
- The Gregorian calendar scale is assumed if this property is not
- specified in the iCalendar object. It is expected that other
- calendar scales will be defined in other specifications or by
- future versions of this memo.
-
- Format Definition: This property is defined by the following
- notation:
-
- calscale = "CALSCALE" calparam ":" calvalue CRLF
-
- calparam = *(";" other-param)
-
- calvalue = "GREGORIAN"
-
- Example: The following is an example of this property:
-
- CALSCALE:GREGORIAN
-
-3.7.2. Method
-
- Property Name: METHOD
-
- Purpose: This property defines the iCalendar object method
- associated with the calendar object.
-
- Value Type: TEXT
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified once in an iCalendar
- object.
-
- Description: When used in a MIME message entity, the value of this
- property MUST be the same as the Content-Type "method" parameter
- value. If either the "METHOD" property or the Content-Type
- "method" parameter is specified, then the other MUST also be
- specified.
-
- No methods are defined by this specification. This is the subject
- of other specifications, such as the iCalendar Transport-
- independent Interoperability Protocol (iTIP) defined by [2446bis].
-
- If this property is not present in the iCalendar object, then a
- scheduling transaction MUST NOT be assumed. In such cases, the
- iCalendar object is merely being used to transport a snapshot of
-
-
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-
-
- some calendar information; without the intention of conveying a
- scheduling semantic.
-
- Format Definition: This property is defined by the following
- notation:
-
- method = "METHOD" metparam ":" metvalue CRLF
-
- metparam = *(";" other-param)
-
- metvalue = iana-token
-
- Example: The following is a hypothetical example of this property to
- convey that the iCalendar object is a scheduling request:
-
- METHOD:REQUEST
-
-3.7.3. Product Identifier
-
- Property Name: PRODID
-
- Purpose: This property specifies the identifier for the product that
- created the iCalendar object.
-
- Value Type: TEXT
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: The property MUST be specified once in an iCalendar
- object.
-
- Description: The vendor of the implementation SHOULD assure that
- this is a globally unique identifier; using some technique such as
- an FPI value, as defined in [ISO.9070.1991].
-
- This property SHOULD NOT be used to alter the interpretation of an
- iCalendar object beyond the semantics specified in this memo. For
- example, it is not to be used to further the understanding of non-
- standard properties.
-
- Format Definition: This property is defined by the following
- notation:
-
- prodid = "PRODID" pidparam ":" pidvalue CRLF
-
- pidparam = *(";" other-param)
-
-
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-
-
- pidvalue = text
- ;Any text that describes the product and version
- ;and that is generally assured of being unique.
-
- Example: The following is an example of this property. It does not
- imply that English is the default language.
-
- PRODID:-//ABC Corporation//NONSGML My Product//EN
-
-3.7.4. Version
-
- Property Name: VERSION
-
- Purpose: This property specifies the identifier corresponding to the
- highest version number or the minimum and maximum range of the
- iCalendar specification that is required in order to interpret the
- iCalendar object.
-
- Value Type: TEXT
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property MUST be specified once in an iCalendar
- object.
-
- Description: A value of "2.0" corresponds to this memo.
-
- Format Definition: This property is defined by the following
- notation:
-
- version = "VERSION" verparam ":" vervalue CRLF
-
- verparam = *(";" other-param)
-
- vervalue = "2.0" ;This memo
- / maxver
- / (minver ";" maxver)
-
- minver = <A IANA-registered iCalendar version identifier>
- ;Minimum iCalendar version needed to parse the iCalendar object.
-
- maxver = <A IANA-registered iCalendar version identifier>
- ;Maximum iCalendar version needed to parse the iCalendar object.
-
-
-
-
-
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-
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-
-
- Example: The following is an example of this property:
-
- VERSION:2.0
-
-3.8. Component Properties
-
- The following properties can appear within calendar components, as
- specified by each component property definition.
-
-3.8.1. Descriptive Component Properties
-
- The following properties specify descriptive information about
- calendar components.
-
-3.8.1.1. Attachment
-
- Property Name: ATTACH
-
- Purpose: This property provides the capability to associate a
- document object with a calendar component.
-
- Value Type: The default value type for this property is URI. The
- value type can also be set to BINARY to indicate inline binary
- encoded content information.
-
- Property Parameters: IANA, non-standard, inline encoding, and value
- data type property parameters can be specified on this property.
- The format type parameter can be specified on this property and is
- RECOMMENDED for inline binary encoded content information.
-
- Conformance: This property can be specified multiple times in a
- "VEVENT", "VTODO", "VJOURNAL", or "VALARM" calendar component with
- the exception of AUDIO alarm that only allows this property to
- occur once.
-
- Description: This property is used in "VEVENT", "VTODO", and
- "VJOURNAL" calendar components to associate a resource (e.g.,
- document) with the calendar component. This property is used in
- "VALARM" calendar components to specify an audio sound resource or
- an email message attachment. This property can be specified as a
- URI pointing to a resource or as inline binary encoded content.
-
- When this property is specified as inline binary encoded content,
- calendar applications MAY attempt to guess the media type of the
- resource via inspection of its content if and only if the media
- type of the resource is not given by the "FMTTYPE" parameter. If
- the media type remains unknown, calendar applications SHOULD treat
- it as type "application/octet-stream".
-
-
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-
-
- Format Definition: This property is defined by the following
- notation:
-
- attach = "ATTACH" attachparam ( ":" uri ) /
- (
- ";" "ENCODING" "=" "BASE64"
- ";" "VALUE" "=" "BINARY"
- ":" binary
- )
- CRLF
-
- attachparam = *(
- ;
- ; The following is OPTIONAL for a URI value,
- ; RECOMMENDED for a BINARY value,
- ; and MUST NOT occur more than once.
- ;
- (";" fmttypeparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following are examples of this property:
-
- ATTACH:CID:jsmith.part3.960817T083000.xyzMail@example.com
-
- ATTACH;FMTTYPE=application/postscript:ftp://example.com/pub/
- reports/r-960812.ps
-
-3.8.1.2. Categories
-
- Property Name: CATEGORIES
-
- Purpose: This property defines the categories for a calendar
- component.
-
- Value Type: TEXT
-
- Property Parameters: IANA, non-standard, and language property
- parameters can be specified on this property.
-
- Conformance: The property can be specified within "VEVENT", "VTODO",
- or "VJOURNAL" calendar components.
-
-
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-
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-
-
- Description: This property is used to specify categories or subtypes
- of the calendar component. The categories are useful in searching
- for a calendar component of a particular type and category.
- Within the "VEVENT", "VTODO", or "VJOURNAL" calendar components,
- more than one category can be specified as a COMMA-separated list
- of categories.
-
- Format Definition: This property is defined by the following
- notation:
-
- categories = "CATEGORIES" catparam ":" text *("," text)
- CRLF
-
- catparam = *(
- ;
- ; The following is OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" languageparam ) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following are examples of this property:
-
- CATEGORIES:APPOINTMENT,EDUCATION
-
- CATEGORIES:MEETING
-
-3.8.1.3. Classification
-
- Property Name: CLASS
-
- Purpose: This property defines the access classification for a
- calendar component.
-
- Value Type: TEXT
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: The property can be specified once in a "VEVENT",
- "VTODO", or "VJOURNAL" calendar components.
-
-
-
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-
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-
-
- Description: An access classification is only one component of the
- general security system within a calendar application. It
- provides a method of capturing the scope of the access the
- calendar owner intends for information within an individual
- calendar entry. The access classification of an individual
- iCalendar component is useful when measured along with the other
- security components of a calendar system (e.g., calendar user
- authentication, authorization, access rights, access role, etc.).
- Hence, the semantics of the individual access classifications
- cannot be completely defined by this memo alone. Additionally,
- due to the "blind" nature of most exchange processes using this
- memo, these access classifications cannot serve as an enforcement
- statement for a system receiving an iCalendar object. Rather,
- they provide a method for capturing the intention of the calendar
- owner for the access to the calendar component. If not specified
- in a component that allows this property, the default value is
- PUBLIC. Applications MUST treat x-name and iana-token values they
- don't recognize the same way as they would the PRIVATE value.
-
- Format Definition: This property is defined by the following
- notation:
-
- class = "CLASS" classparam ":" classvalue CRLF
-
- classparam = *(";" other-param)
-
- classvalue = "PUBLIC" / "PRIVATE" / "CONFIDENTIAL" / iana-token
- / x-name
- ;Default is PUBLIC
-
- Example: The following is an example of this property:
-
- CLASS:PUBLIC
-
-3.8.1.4. Comment
-
- Property Name: COMMENT
-
- Purpose: This property specifies non-processing information intended
- to provide a comment to the calendar user.
-
- Value Type: TEXT
-
- Property Parameters: IANA, non-standard, alternate text
- representation, and language property parameters can be specified
- on this property.
-
-
-
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-
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-
-
- Conformance: This property can be specified multiple times in
- "VEVENT", "VTODO", "VJOURNAL", and "VFREEBUSY" calendar components
- as well as in the "STANDARD" and "DAYLIGHT" sub-components.
-
- Description: This property is used to specify a comment to the
- calendar user.
-
- Format Definition: This property is defined by the following
- notation:
-
- comment = "COMMENT" commparam ":" text CRLF
-
- commparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" altrepparam) / (";" languageparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following is an example of this property:
-
- COMMENT:The meeting really needs to include both ourselves
- and the customer. We can't hold this meeting without them.
- As a matter of fact\, the venue for the meeting ought to be at
- their site. - - John
-
-3.8.1.5. Description
-
- Property Name: DESCRIPTION
-
- Purpose: This property provides a more complete description of the
- calendar component than that provided by the "SUMMARY" property.
-
- Value Type: TEXT
-
- Property Parameters: IANA, non-standard, alternate text
- representation, and language property parameters can be specified
- on this property.
-
-
-
-
-
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-
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-
-
- Conformance: The property can be specified in the "VEVENT", "VTODO",
- "VJOURNAL", or "VALARM" calendar components. The property can be
- specified multiple times only within a "VJOURNAL" calendar
- component.
-
- Description: This property is used in the "VEVENT" and "VTODO" to
- capture lengthy textual descriptions associated with the activity.
-
- This property is used in the "VJOURNAL" calendar component to
- capture one or more textual journal entries.
-
- This property is used in the "VALARM" calendar component to
- capture the display text for a DISPLAY category of alarm, and to
- capture the body text for an EMAIL category of alarm.
-
- Format Definition: This property is defined by the following
- notation:
-
- description = "DESCRIPTION" descparam ":" text CRLF
-
- descparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" altrepparam) / (";" languageparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following is an example of this property with formatted
- line breaks in the property value:
-
- DESCRIPTION:Meeting to provide technical review for "Phoenix"
- design.\nHappy Face Conference Room. Phoenix design team
- MUST attend this meeting.\nRSVP to team leader.
-
-3.8.1.6. Geographic Position
-
- Property Name: GEO
-
- Purpose: This property specifies information related to the global
- position for the activity specified by a calendar component.
-
-
-
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-
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-
-
- Value Type: FLOAT. The value MUST be two SEMICOLON-separated FLOAT
- values.
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified in "VEVENT" or "VTODO"
- calendar components.
-
- Description: This property value specifies latitude and longitude,
- in that order (i.e., "LAT LON" ordering). The longitude
- represents the location east or west of the prime meridian as a
- positive or negative real number, respectively. The longitude and
- latitude values MAY be specified up to six decimal places, which
- will allow for accuracy to within one meter of geographical
- position. Receiving applications MUST accept values of this
- precision and MAY truncate values of greater precision.
-
- Values for latitude and longitude shall be expressed as decimal
- fractions of degrees. Whole degrees of latitude shall be
- represented by a two-digit decimal number ranging from 0 through
- 90. Whole degrees of longitude shall be represented by a decimal
- number ranging from 0 through 180. When a decimal fraction of a
- degree is specified, it shall be separated from the whole number
- of degrees by a decimal point.
-
- Latitudes north of the equator shall be specified by a plus sign
- (+), or by the absence of a minus sign (-), preceding the digits
- designating degrees. Latitudes south of the Equator shall be
- designated by a minus sign (-) preceding the digits designating
- degrees. A point on the Equator shall be assigned to the Northern
- Hemisphere.
-
- Longitudes east of the prime meridian shall be specified by a plus
- sign (+), or by the absence of a minus sign (-), preceding the
- digits designating degrees. Longitudes west of the meridian shall
- be designated by minus sign (-) preceding the digits designating
- degrees. A point on the prime meridian shall be assigned to the
- Eastern Hemisphere. A point on the 180th meridian shall be
- assigned to the Western Hemisphere. One exception to this last
- convention is permitted. For the special condition of describing
- a band of latitude around the earth, the East Bounding Coordinate
- data element shall be assigned the value +180 (180) degrees.
-
- Any spatial address with a latitude of +90 (90) or -90 degrees
- will specify the position at the North or South Pole,
- respectively. The component for longitude may have any legal
- value.
-
-
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-
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-
-
- With the exception of the special condition described above, this
- form is specified in [ANSI INCITS 61-1986].
-
- The simple formula for converting degrees-minutes-seconds into
- decimal degrees is:
-
- decimal = degrees + minutes/60 + seconds/3600.
-
- Format Definition: This property is defined by the following
- notation:
-
- geo = "GEO" geoparam ":" geovalue CRLF
-
- geoparam = *(";" other-param)
-
- geovalue = float ";" float
- ;Latitude and Longitude components
-
- Example: The following is an example of this property:
-
- GEO:37.386013;-122.082932
-
-3.8.1.7. Location
-
- Property Name: LOCATION
-
- Purpose: This property defines the intended venue for the activity
- defined by a calendar component.
-
- Value Type: TEXT
-
- Property Parameters: IANA, non-standard, alternate text
- representation, and language property parameters can be specified
- on this property.
-
- Conformance: This property can be specified in "VEVENT" or "VTODO"
- calendar component.
-
- Description: Specific venues such as conference or meeting rooms may
- be explicitly specified using this property. An alternate
- representation may be specified that is a URI that points to
- directory information with more structured specification of the
- location. For example, the alternate representation may specify
- either an LDAP URL [RFC4516] pointing to an LDAP server entry or a
- CID URL [RFC2392] pointing to a MIME body part containing a
- Virtual-Information Card (vCard) [RFC2426] for the location.
-
-
-
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-
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-
-
- Format Definition: This property is defined by the following
- notation:
-
- location = "LOCATION" locparam ":" text CRLF
-
- locparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" altrepparam) / (";" languageparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following are some examples of this property:
-
- LOCATION:Conference Room - F123\, Bldg. 002
-
- LOCATION;ALTREP="http://xyzcorp.com/conf-rooms/f123.vcf":
- Conference Room - F123\, Bldg. 002
-
-3.8.1.8. Percent Complete
-
- Property Name: PERCENT-COMPLETE
-
- Purpose: This property is used by an assignee or delegatee of a
- to-do to convey the percent completion of a to-do to the
- "Organizer".
-
- Value Type: INTEGER
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified once in a "VTODO"
- calendar component.
-
- Description: The property value is a positive integer between 0 and
- 100. A value of "0" indicates the to-do has not yet been started.
- A value of "100" indicates that the to-do has been completed.
- Integer values in between indicate the percent partially complete.
-
-
-
-
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-
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-
-
- When a to-do is assigned to multiple individuals, the property
- value indicates the percent complete for that portion of the to-do
- assigned to the assignee or delegatee. For example, if a to-do is
- assigned to both individuals "A" and "B". A reply from "A" with a
- percent complete of "70" indicates that "A" has completed 70% of
- the to-do assigned to them. A reply from "B" with a percent
- complete of "50" indicates "B" has completed 50% of the to-do
- assigned to them.
-
- Format Definition: This property is defined by the following
- notation:
-
- percent = "PERCENT-COMPLETE" pctparam ":" integer CRLF
-
- pctparam = *(";" other-param)
-
- Example: The following is an example of this property to show 39%
- completion:
-
- PERCENT-COMPLETE:39
-
-3.8.1.9. Priority
-
- Property Name: PRIORITY
-
- Purpose: This property defines the relative priority for a calendar
- component.
-
- Value Type: INTEGER
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified in "VEVENT" and "VTODO"
- calendar components.
-
- Description: This priority is specified as an integer in the range 0
- to 9. A value of 0 specifies an undefined priority. A value of 1
- is the highest priority. A value of 2 is the second highest
- priority. Subsequent numbers specify a decreasing ordinal
- priority. A value of 9 is the lowest priority.
-
- A CUA with a three-level priority scheme of "HIGH", "MEDIUM", and
- "LOW" is mapped into this property such that a property value in
- the range of 1 to 4 specifies "HIGH" priority. A value of 5 is
- the normal or "MEDIUM" priority. A value in the range of 6 to 9
- is "LOW" priority.
-
-
-
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-
-
- A CUA with a priority schema of "A1", "A2", "A3", "B1", "B2", ...,
- "C3" is mapped into this property such that a property value of 1
- specifies "A1", a property value of 2 specifies "A2", a property
- value of 3 specifies "A3", and so forth up to a property value of
- 9 specifies "C3".
-
- Other integer values are reserved for future use.
-
- Within a "VEVENT" calendar component, this property specifies a
- priority for the event. This property may be useful when more
- than one event is scheduled for a given time period.
-
- Within a "VTODO" calendar component, this property specified a
- priority for the to-do. This property is useful in prioritizing
- multiple action items for a given time period.
-
- Format Definition: This property is defined by the following
- notation:
-
- priority = "PRIORITY" prioparam ":" priovalue CRLF
- ;Default is zero (i.e., undefined).
-
- prioparam = *(";" other-param)
-
- priovalue = integer ;Must be in the range [0..9]
- ; All other values are reserved for future use.
-
- Example: The following is an example of a property with the highest
- priority:
-
- PRIORITY:1
-
- The following is an example of a property with a next highest
- priority:
-
- PRIORITY:2
-
- The following is an example of a property with no priority. This
- is equivalent to not specifying the "PRIORITY" property:
-
- PRIORITY:0
-
-
-
-
-
-
-
-
-
-
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-
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-
-
-3.8.1.10. Resources
-
- Property Name: RESOURCES
-
- Purpose: This property defines the equipment or resources
- anticipated for an activity specified by a calendar component.
-
- Value Type: TEXT
-
- Property Parameters: IANA, non-standard, alternate text
- representation, and language property parameters can be specified
- on this property.
-
- Conformance: This property can be specified once in "VEVENT" or
- "VTODO" calendar component.
-
- Description: The property value is an arbitrary text. More than one
- resource can be specified as a COMMA-separated list of resources.
-
- Format Definition: This property is defined by the following
- notation:
-
- resources = "RESOURCES" resrcparam ":" text *("," text) CRLF
-
- resrcparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" altrepparam) / (";" languageparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following is an example of this property:
-
- RESOURCES:EASEL,PROJECTOR,VCR
-
- RESOURCES;LANGUAGE=fr:Nettoyeur haute pression
-
-
-
-
-
-
-
-
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-
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-
-
-3.8.1.11. Status
-
- Property Name: STATUS
-
- Purpose: This property defines the overall status or confirmation
- for the calendar component.
-
- Value Type: TEXT
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified once in "VEVENT",
- "VTODO", or "VJOURNAL" calendar components.
-
- Description: In a group-scheduled calendar component, the property
- is used by the "Organizer" to provide a confirmation of the event
- to the "Attendees". For example in a "VEVENT" calendar component,
- the "Organizer" can indicate that a meeting is tentative,
- confirmed, or cancelled. In a "VTODO" calendar component, the
- "Organizer" can indicate that an action item needs action, is
- completed, is in process or being worked on, or has been
- cancelled. In a "VJOURNAL" calendar component, the "Organizer"
- can indicate that a journal entry is draft, final, or has been
- cancelled or removed.
-
- Format Definition: This property is defined by the following
- notation:
-
- status = "STATUS" statparam ":" statvalue CRLF
-
- statparam = *(";" other-param)
-
- statvalue = (statvalue-event
- / statvalue-todo
- / statvalue-jour)
-
- statvalue-event = "TENTATIVE" ;Indicates event is tentative.
- / "CONFIRMED" ;Indicates event is definite.
- / "CANCELLED" ;Indicates event was cancelled.
- ;Status values for a "VEVENT"
-
- statvalue-todo = "NEEDS-ACTION" ;Indicates to-do needs action.
- / "COMPLETED" ;Indicates to-do completed.
- / "IN-PROCESS" ;Indicates to-do in process of.
- / "CANCELLED" ;Indicates to-do was cancelled.
- ;Status values for "VTODO".
-
-
-
-
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-
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-
-
- statvalue-jour = "DRAFT" ;Indicates journal is draft.
- / "FINAL" ;Indicates journal is final.
- / "CANCELLED" ;Indicates journal is removed.
- ;Status values for "VJOURNAL".
-
- Example: The following is an example of this property for a "VEVENT"
- calendar component:
-
- STATUS:TENTATIVE
-
- The following is an example of this property for a "VTODO"
- calendar component:
-
- STATUS:NEEDS-ACTION
-
- The following is an example of this property for a "VJOURNAL"
- calendar component:
-
- STATUS:DRAFT
-
-3.8.1.12. Summary
-
- Property Name: SUMMARY
-
- Purpose: This property defines a short summary or subject for the
- calendar component.
-
- Value Type: TEXT
-
- Property Parameters: IANA, non-standard, alternate text
- representation, and language property parameters can be specified
- on this property.
-
- Conformance: The property can be specified in "VEVENT", "VTODO",
- "VJOURNAL", or "VALARM" calendar components.
-
- Description: This property is used in the "VEVENT", "VTODO", and
- "VJOURNAL" calendar components to capture a short, one-line
- summary about the activity or journal entry.
-
- This property is used in the "VALARM" calendar component to
- capture the subject of an EMAIL category of alarm.
-
- Format Definition: This property is defined by the following
- notation:
-
-
-
-
-
-
-Desruisseaux Standards Track [Page 93]
-
-RFC 5545 iCalendar September 2009
-
-
- summary = "SUMMARY" summparam ":" text CRLF
-
- summparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" altrepparam) / (";" languageparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following is an example of this property:
-
- SUMMARY:Department Party
-
-3.8.2. Date and Time Component Properties
-
- The following properties specify date and time related information in
- calendar components.
-
-3.8.2.1. Date-Time Completed
-
- Property Name: COMPLETED
-
- Purpose: This property defines the date and time that a to-do was
- actually completed.
-
- Value Type: DATE-TIME
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: The property can be specified in a "VTODO" calendar
- component. The value MUST be specified as a date with UTC time.
-
- Description: This property defines the date and time that a to-do
- was actually completed.
-
- Format Definition: This property is defined by the following
- notation:
-
-
-
-
-
-
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-
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-
-
- completed = "COMPLETED" compparam ":" date-time CRLF
-
- compparam = *(";" other-param)
-
- Example: The following is an example of this property:
-
- COMPLETED:19960401T150000Z
-
-3.8.2.2. Date-Time End
-
- Property Name: DTEND
-
- Purpose: This property specifies the date and time that a calendar
- component ends.
-
- Value Type: The default value type is DATE-TIME. The value type can
- be set to a DATE value type.
-
- Property Parameters: IANA, non-standard, value data type, and time
- zone identifier property parameters can be specified on this
- property.
-
- Conformance: This property can be specified in "VEVENT" or
- "VFREEBUSY" calendar components.
-
- Description: Within the "VEVENT" calendar component, this property
- defines the date and time by which the event ends. The value type
- of this property MUST be the same as the "DTSTART" property, and
- its value MUST be later in time than the value of the "DTSTART"
- property. Furthermore, this property MUST be specified as a date
- with local time if and only if the "DTSTART" property is also
- specified as a date with local time.
-
- Within the "VFREEBUSY" calendar component, this property defines
- the end date and time for the free or busy time information. The
- time MUST be specified in the UTC time format. The value MUST be
- later in time than the value of the "DTSTART" property.
-
- Format Definition: This property is defined by the following
- notation:
-
-
-
-
-
-
-
-
-
-
-
-Desruisseaux Standards Track [Page 95]
-
-RFC 5545 iCalendar September 2009
-
-
- dtend = "DTEND" dtendparam ":" dtendval CRLF
-
- dtendparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
- (";" tzidparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- dtendval = date-time / date
- ;Value MUST match value type
-
- Example: The following is an example of this property:
-
- DTEND:19960401T150000Z
-
- DTEND;VALUE=DATE:19980704
-
-3.8.2.3. Date-Time Due
-
- Property Name: DUE
-
- Purpose: This property defines the date and time that a to-do is
- expected to be completed.
-
- Value Type: The default value type is DATE-TIME. The value type can
- be set to a DATE value type.
-
- Property Parameters: IANA, non-standard, value data type, and time
- zone identifier property parameters can be specified on this
- property.
-
- Conformance: The property can be specified once in a "VTODO"
- calendar component.
-
- Description: This property defines the date and time before which a
- to-do is expected to be completed. For cases where this property
- is specified in a "VTODO" calendar component that also specifies a
- "DTSTART" property, the value type of this property MUST be the
- same as the "DTSTART" property, and the value of this property
-
-
-
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-
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-
-
- MUST be later in time than the value of the "DTSTART" property.
- Furthermore, this property MUST be specified as a date with local
- time if and only if the "DTSTART" property is also specified as a
- date with local time.
-
- Format Definition: This property is defined by the following
- notation:
-
- due = "DUE" dueparam ":" dueval CRLF
-
- dueparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
- (";" tzidparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- dueval = date-time / date
- ;Value MUST match value type
-
- Example: The following is an example of this property:
-
- DUE:19980430T000000Z
-
-3.8.2.4. Date-Time Start
-
- Property Name: DTSTART
-
- Purpose: This property specifies when the calendar component begins.
-
- Value Type: The default value type is DATE-TIME. The time value
- MUST be one of the forms defined for the DATE-TIME value type.
- The value type can be set to a DATE value type.
-
- Property Parameters: IANA, non-standard, value data type, and time
- zone identifier property parameters can be specified on this
- property.
-
- Conformance: This property can be specified once in the "VEVENT",
- "VTODO", or "VFREEBUSY" calendar components as well as in the
-
-
-
-Desruisseaux Standards Track [Page 97]
-
-RFC 5545 iCalendar September 2009
-
-
- "STANDARD" and "DAYLIGHT" sub-components. This property is
- REQUIRED in all types of recurring calendar components that
- specify the "RRULE" property. This property is also REQUIRED in
- "VEVENT" calendar components contained in iCalendar objects that
- don't specify the "METHOD" property.
-
- Description: Within the "VEVENT" calendar component, this property
- defines the start date and time for the event.
-
- Within the "VFREEBUSY" calendar component, this property defines
- the start date and time for the free or busy time information.
- The time MUST be specified in UTC time.
-
- Within the "STANDARD" and "DAYLIGHT" sub-components, this property
- defines the effective start date and time for a time zone
- specification. This property is REQUIRED within each "STANDARD"
- and "DAYLIGHT" sub-components included in "VTIMEZONE" calendar
- components and MUST be specified as a date with local time without
- the "TZID" property parameter.
-
- Format Definition: This property is defined by the following
- notation:
-
- dtstart = "DTSTART" dtstparam ":" dtstval CRLF
-
- dtstparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
- (";" tzidparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- dtstval = date-time / date
- ;Value MUST match value type
-
- Example: The following is an example of this property:
-
- DTSTART:19980118T073000Z
-
-
-
-
-
-Desruisseaux Standards Track [Page 98]
-
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-
-
-3.8.2.5. Duration
-
- Property Name: DURATION
-
- Purpose: This property specifies a positive duration of time.
-
- Value Type: DURATION
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified in "VEVENT", "VTODO", or
- "VALARM" calendar components.
-
- Description: In a "VEVENT" calendar component the property may be
- used to specify a duration of the event, instead of an explicit
- end DATE-TIME. In a "VTODO" calendar component the property may
- be used to specify a duration for the to-do, instead of an
- explicit due DATE-TIME. In a "VALARM" calendar component the
- property may be used to specify the delay period prior to
- repeating an alarm. When the "DURATION" property relates to a
- "DTSTART" property that is specified as a DATE value, then the
- "DURATION" property MUST be specified as a "dur-day" or "dur-week"
- value.
-
- Format Definition: This property is defined by the following
- notation:
-
- duration = "DURATION" durparam ":" dur-value CRLF
- ;consisting of a positive duration of time.
-
- durparam = *(";" other-param)
-
- Example: The following is an example of this property that specifies
- an interval of time of one hour and zero minutes and zero seconds:
-
- DURATION:PT1H0M0S
-
- The following is an example of this property that specifies an
- interval of time of 15 minutes.
-
- DURATION:PT15M
-
-
-
-
-
-
-
-
-
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-
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-
-
-3.8.2.6. Free/Busy Time
-
- Property Name: FREEBUSY
-
- Purpose: This property defines one or more free or busy time
- intervals.
-
- Value Type: PERIOD
-
- Property Parameters: IANA, non-standard, and free/busy time type
- property parameters can be specified on this property.
-
- Conformance: The property can be specified in a "VFREEBUSY" calendar
- component.
-
- Description: These time periods can be specified as either a start
- and end DATE-TIME or a start DATE-TIME and DURATION. The date and
- time MUST be a UTC time format.
-
- "FREEBUSY" properties within the "VFREEBUSY" calendar component
- SHOULD be sorted in ascending order, based on start time and then
- end time, with the earliest periods first.
-
- The "FREEBUSY" property can specify more than one value, separated
- by the COMMA character. In such cases, the "FREEBUSY" property
- values MUST all be of the same "FBTYPE" property parameter type
- (e.g., all values of a particular "FBTYPE" listed together in a
- single property).
-
- Format Definition: This property is defined by the following
- notation:
-
- freebusy = "FREEBUSY" fbparam ":" fbvalue CRLF
-
- fbparam = *(
- ;
- ; The following is OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" fbtypeparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- fbvalue = period *("," period)
- ;Time value MUST be in the UTC time format.
-
- Example: The following are some examples of this property:
-
- FREEBUSY;FBTYPE=BUSY-UNAVAILABLE:19970308T160000Z/PT8H30M
-
- FREEBUSY;FBTYPE=FREE:19970308T160000Z/PT3H,19970308T200000Z/PT1H
-
- FREEBUSY;FBTYPE=FREE:19970308T160000Z/PT3H,19970308T200000Z/PT1H
- ,19970308T230000Z/19970309T000000Z
-
-3.8.2.7. Time Transparency
-
- Property Name: TRANSP
-
- Purpose: This property defines whether or not an event is
- transparent to busy time searches.
-
- Value Type: TEXT
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified once in a "VEVENT"
- calendar component.
-
- Description: Time Transparency is the characteristic of an event
- that determines whether it appears to consume time on a calendar.
- Events that consume actual time for the individual or resource
- associated with the calendar SHOULD be recorded as OPAQUE,
- allowing them to be detected by free/busy time searches. Other
- events, which do not take up the individual's (or resource's) time
- SHOULD be recorded as TRANSPARENT, making them invisible to free/
- busy time searches.
-
- Format Definition: This property is defined by the following
- notation:
-
- transp = "TRANSP" transparam ":" transvalue CRLF
-
- transparam = *(";" other-param)
-
- transvalue = "OPAQUE"
- ;Blocks or opaque on busy time searches.
- / "TRANSPARENT"
- ;Transparent on busy time searches.
- ;Default value is OPAQUE
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Example: The following is an example of this property for an event
- that is transparent or does not block on free/busy time searches:
-
- TRANSP:TRANSPARENT
-
- The following is an example of this property for an event that is
- opaque or blocks on free/busy time searches:
-
- TRANSP:OPAQUE
-
-3.8.3. Time Zone Component Properties
-
- The following properties specify time zone information in calendar
- components.
-
-3.8.3.1. Time Zone Identifier
-
- Property Name: TZID
-
- Purpose: This property specifies the text value that uniquely
- identifies the "VTIMEZONE" calendar component in the scope of an
- iCalendar object.
-
- Value Type: TEXT
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property MUST be specified in a "VTIMEZONE"
- calendar component.
-
- Description: This is the label by which a time zone calendar
- component is referenced by any iCalendar properties whose value
- type is either DATE-TIME or TIME and not intended to specify a UTC
- or a "floating" time. The presence of the SOLIDUS character as a
- prefix, indicates that this "TZID" represents an unique ID in a
- globally defined time zone registry (when such registry is
- defined).
-
- Note: This document does not define a naming convention for
- time zone identifiers. Implementers may want to use the naming
- conventions defined in existing time zone specifications such
- as the public-domain TZ database [TZDB]. The specification of
- globally unique time zone identifiers is not addressed by this
- document and is left for future study.
-
-
-
-
-
-
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-
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-
-
- Format Definition: This property is defined by the following
- notation:
-
- tzid = "TZID" tzidpropparam ":" [tzidprefix] text CRLF
-
- tzidpropparam = *(";" other-param)
-
- ;tzidprefix = "/"
- ; Defined previously. Just listed here for reader convenience.
-
- Example: The following are examples of non-globally unique time zone
- identifiers:
-
- TZID:America/New_York
-
- TZID:America/Los_Angeles
-
- The following is an example of a fictitious globally unique time
- zone identifier:
-
- TZID:/example.org/America/New_York
-
-3.8.3.2. Time Zone Name
-
- Property Name: TZNAME
-
- Purpose: This property specifies the customary designation for a
- time zone description.
-
- Value Type: TEXT
-
- Property Parameters: IANA, non-standard, and language property
- parameters can be specified on this property.
-
- Conformance: This property can be specified in "STANDARD" and
- "DAYLIGHT" sub-components.
-
- Description: This property specifies a customary name that can be
- used when displaying dates that occur during the observance
- defined by the time zone sub-component.
-
- Format Definition: This property is defined by the following
- notation:
-
-
-
-
-
-
-
-
-Desruisseaux Standards Track [Page 103]
-
-RFC 5545 iCalendar September 2009
-
-
- tzname = "TZNAME" tznparam ":" text CRLF
-
- tznparam = *(
- ;
- ; The following is OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" languageparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following are examples of this property:
-
- TZNAME:EST
-
- TZNAME;LANGUAGE=fr-CA:HNE
-
-3.8.3.3. Time Zone Offset From
-
- Property Name: TZOFFSETFROM
-
- Purpose: This property specifies the offset that is in use prior to
- this time zone observance.
-
- Value Type: UTC-OFFSET
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property MUST be specified in "STANDARD" and
- "DAYLIGHT" sub-components.
-
- Description: This property specifies the offset that is in use prior
- to this time observance. It is used to calculate the absolute
- time at which the transition to a given observance takes place.
- This property MUST only be specified in a "VTIMEZONE" calendar
- component. A "VTIMEZONE" calendar component MUST include this
- property. The property value is a signed numeric indicating the
- number of hours and possibly minutes from UTC. Positive numbers
- represent time zones east of the prime meridian, or ahead of UTC.
- Negative numbers represent time zones west of the prime meridian,
- or behind UTC.
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Format Definition: This property is defined by the following
- notation:
-
- tzoffsetfrom = "TZOFFSETFROM" frmparam ":" utc-offset
- CRLF
-
- frmparam = *(";" other-param)
-
- Example: The following are examples of this property:
-
- TZOFFSETFROM:-0500
-
- TZOFFSETFROM:+1345
-
-3.8.3.4. Time Zone Offset To
-
- Property Name: TZOFFSETTO
-
- Purpose: This property specifies the offset that is in use in this
- time zone observance.
-
- Value Type: UTC-OFFSET
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property MUST be specified in "STANDARD" and
- "DAYLIGHT" sub-components.
-
- Description: This property specifies the offset that is in use in
- this time zone observance. It is used to calculate the absolute
- time for the new observance. The property value is a signed
- numeric indicating the number of hours and possibly minutes from
- UTC. Positive numbers represent time zones east of the prime
- meridian, or ahead of UTC. Negative numbers represent time zones
- west of the prime meridian, or behind UTC.
-
- Format Definition: This property is defined by the following
- notation:
-
- tzoffsetto = "TZOFFSETTO" toparam ":" utc-offset CRLF
-
- toparam = *(";" other-param)
-
-
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Example: The following are examples of this property:
-
- TZOFFSETTO:-0400
-
- TZOFFSETTO:+1245
-
-3.8.3.5. Time Zone URL
-
- Property Name: TZURL
-
- Purpose: This property provides a means for a "VTIMEZONE" component
- to point to a network location that can be used to retrieve an up-
- to-date version of itself.
-
- Value Type: URI
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified in a "VTIMEZONE"
- calendar component.
-
- Description: This property provides a means for a "VTIMEZONE"
- component to point to a network location that can be used to
- retrieve an up-to-date version of itself. This provides a hook to
- handle changes government bodies impose upon time zone
- definitions. Retrieval of this resource results in an iCalendar
- object containing a single "VTIMEZONE" component and a "METHOD"
- property set to PUBLISH.
-
- Format Definition: This property is defined by the following
- notation:
-
- tzurl = "TZURL" tzurlparam ":" uri CRLF
-
- tzurlparam = *(";" other-param)
-
- Example: The following is an example of this property:
-
- TZURL:http://timezones.example.org/tz/America-Los_Angeles.ics
-
-3.8.4. Relationship Component Properties
-
- The following properties specify relationship information in calendar
- components.
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
-3.8.4.1. Attendee
-
- Property Name: ATTENDEE
-
- Purpose: This property defines an "Attendee" within a calendar
- component.
-
- Value Type: CAL-ADDRESS
-
- Property Parameters: IANA, non-standard, language, calendar user
- type, group or list membership, participation role, participation
- status, RSVP expectation, delegatee, delegator, sent by, common
- name, or directory entry reference property parameters can be
- specified on this property.
-
- Conformance: This property MUST be specified in an iCalendar object
- that specifies a group-scheduled calendar entity. This property
- MUST NOT be specified in an iCalendar object when publishing the
- calendar information (e.g., NOT in an iCalendar object that
- specifies the publication of a calendar user's busy time, event,
- to-do, or journal). This property is not specified in an
- iCalendar object that specifies only a time zone definition or
- that defines calendar components that are not group-scheduled
- components, but are components only on a single user's calendar.
-
- Description: This property MUST only be specified within calendar
- components to specify participants, non-participants, and the
- chair of a group-scheduled calendar entity. The property is
- specified within an "EMAIL" category of the "VALARM" calendar
- component to specify an email address that is to receive the email
- type of iCalendar alarm.
-
- The property parameter "CN" is for the common or displayable name
- associated with the calendar address; "ROLE", for the intended
- role that the attendee will have in the calendar component;
- "PARTSTAT", for the status of the attendee's participation;
- "RSVP", for indicating whether the favor of a reply is requested;
- "CUTYPE", to indicate the type of calendar user; "MEMBER", to
- indicate the groups that the attendee belongs to; "DELEGATED-TO",
- to indicate the calendar users that the original request was
- delegated to; and "DELEGATED-FROM", to indicate whom the request
- was delegated from; "SENT-BY", to indicate whom is acting on
- behalf of the "ATTENDEE"; and "DIR", to indicate the URI that
- points to the directory information corresponding to the attendee.
- These property parameters can be specified on an "ATTENDEE"
- property in either a "VEVENT", "VTODO", or "VJOURNAL" calendar
- component. They MUST NOT be specified in an "ATTENDEE" property
- in a "VFREEBUSY" or "VALARM" calendar component. If the
-
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-
- "LANGUAGE" property parameter is specified, the identified
- language applies to the "CN" parameter.
-
- A recipient delegated a request MUST inherit the "RSVP" and "ROLE"
- values from the attendee that delegated the request to them.
-
- Multiple attendees can be specified by including multiple
- "ATTENDEE" properties within the calendar component.
-
- Format Definition: This property is defined by the following
- notation:
-
- attendee = "ATTENDEE" attparam ":" cal-address CRLF
-
- attparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" cutypeparam) / (";" memberparam) /
- (";" roleparam) / (";" partstatparam) /
- (";" rsvpparam) / (";" deltoparam) /
- (";" delfromparam) / (";" sentbyparam) /
- (";" cnparam) / (";" dirparam) /
- (";" languageparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following are examples of this property's use for a
- to-do:
-
- ATTENDEE;MEMBER="mailto:DEV-GROUP@example.com":
- mailto:joecool@example.com
- ATTENDEE;DELEGATED-FROM="mailto:immud@example.com":
- mailto:ildoit@example.com
-
-
-
-
-
-
-
-
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-
- The following is an example of this property used for specifying
- multiple attendees to an event:
-
- ATTENDEE;ROLE=REQ-PARTICIPANT;PARTSTAT=TENTATIVE;CN=Henry
- Cabot:mailto:hcabot@example.com
- ATTENDEE;ROLE=REQ-PARTICIPANT;DELEGATED-FROM="mailto:bob@
- example.com";PARTSTAT=ACCEPTED;CN=Jane Doe:mailto:jdoe@
- example.com
-
- The following is an example of this property with a URI to the
- directory information associated with the attendee:
-
- ATTENDEE;CN=John Smith;DIR="ldap://example.com:6666/o=ABC%
- 20Industries,c=US???(cn=Jim%20Dolittle)":mailto:jimdo@
- example.com
-
- The following is an example of this property with "delegatee" and
- "delegator" information for an event:
-
- ATTENDEE;ROLE=REQ-PARTICIPANT;PARTSTAT=TENTATIVE;DELEGATED-FROM=
- "mailto:iamboss@example.com";CN=Henry Cabot:mailto:hcabot@
- example.com
- ATTENDEE;ROLE=NON-PARTICIPANT;PARTSTAT=DELEGATED;DELEGATED-TO=
- "mailto:hcabot@example.com";CN=The Big Cheese:mailto:iamboss
- @example.com
- ATTENDEE;ROLE=REQ-PARTICIPANT;PARTSTAT=ACCEPTED;CN=Jane Doe
- :mailto:jdoe@example.com
-
- Example: The following is an example of this property's use when
- another calendar user is acting on behalf of the "Attendee":
-
- ATTENDEE;SENT-BY=mailto:jan_doe@example.com;CN=John Smith:
- mailto:jsmith@example.com
-
-3.8.4.2. Contact
-
- Property Name: CONTACT
-
- Purpose: This property is used to represent contact information or
- alternately a reference to contact information associated with the
- calendar component.
-
- Value Type: TEXT
-
- Property Parameters: IANA, non-standard, alternate text
- representation, and language property parameters can be specified
- on this property.
-
-
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-
- Conformance: This property can be specified in a "VEVENT", "VTODO",
- "VJOURNAL", or "VFREEBUSY" calendar component.
-
- Description: The property value consists of textual contact
- information. An alternative representation for the property value
- can also be specified that refers to a URI pointing to an
- alternate form, such as a vCard [RFC2426], for the contact
- information.
-
- Format Definition: This property is defined by the following
- notation:
-
- contact = "CONTACT" contparam ":" text CRLF
-
- contparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" altrepparam) / (";" languageparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following is an example of this property referencing
- textual contact information:
-
- CONTACT:Jim Dolittle\, ABC Industries\, +1-919-555-1234
-
- The following is an example of this property with an alternate
- representation of an LDAP URI to a directory entry containing the
- contact information:
-
- CONTACT;ALTREP="ldap://example.com:6666/o=ABC%20Industries\,
- c=US???(cn=Jim%20Dolittle)":Jim Dolittle\, ABC Industries\,
- +1-919-555-1234
-
- The following is an example of this property with an alternate
- representation of a MIME body part containing the contact
- information, such as a vCard [RFC2426] embedded in a text/
- directory media type [RFC2425]:
-
- CONTACT;ALTREP="CID:part3.msg970930T083000SILVER@example.com":
- Jim Dolittle\, ABC Industries\, +1-919-555-1234
-
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-
- The following is an example of this property referencing a network
- resource, such as a vCard [RFC2426] object containing the contact
- information:
-
- CONTACT;ALTREP="http://example.com/pdi/jdoe.vcf":Jim
- Dolittle\, ABC Industries\, +1-919-555-1234
-
-3.8.4.3. Organizer
-
- Property Name: ORGANIZER
-
- Purpose: This property defines the organizer for a calendar
- component.
-
- Value Type: CAL-ADDRESS
-
- Property Parameters: IANA, non-standard, language, common name,
- directory entry reference, and sent-by property parameters can be
- specified on this property.
-
- Conformance: This property MUST be specified in an iCalendar object
- that specifies a group-scheduled calendar entity. This property
- MUST be specified in an iCalendar object that specifies the
- publication of a calendar user's busy time. This property MUST
- NOT be specified in an iCalendar object that specifies only a time
- zone definition or that defines calendar components that are not
- group-scheduled components, but are components only on a single
- user's calendar.
-
- Description: This property is specified within the "VEVENT",
- "VTODO", and "VJOURNAL" calendar components to specify the
- organizer of a group-scheduled calendar entity. The property is
- specified within the "VFREEBUSY" calendar component to specify the
- calendar user requesting the free or busy time. When publishing a
- "VFREEBUSY" calendar component, the property is used to specify
- the calendar that the published busy time came from.
-
- The property has the property parameters "CN", for specifying the
- common or display name associated with the "Organizer", "DIR", for
- specifying a pointer to the directory information associated with
- the "Organizer", "SENT-BY", for specifying another calendar user
- that is acting on behalf of the "Organizer". The non-standard
- parameters may also be specified on this property. If the
- "LANGUAGE" property parameter is specified, the identified
- language applies to the "CN" parameter value.
-
-
-
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-
-
- Format Definition: This property is defined by the following
- notation:
-
- organizer = "ORGANIZER" orgparam ":"
- cal-address CRLF
-
- orgparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" cnparam) / (";" dirparam) / (";" sentbyparam) /
- (";" languageparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- Example: The following is an example of this property:
-
- ORGANIZER;CN=John Smith:mailto:jsmith@example.com
-
- The following is an example of this property with a pointer to the
- directory information associated with the organizer:
-
- ORGANIZER;CN=JohnSmith;DIR="ldap://example.com:6666/o=DC%20Ass
- ociates,c=US???(cn=John%20Smith)":mailto:jsmith@example.com
-
- The following is an example of this property used by another
- calendar user who is acting on behalf of the organizer, with
- responses intended to be sent back to the organizer, not the other
- calendar user:
-
- ORGANIZER;SENT-BY="mailto:jane_doe@example.com":
- mailto:jsmith@example.com
-
-3.8.4.4. Recurrence ID
-
- Property Name: RECURRENCE-ID
-
- Purpose: This property is used in conjunction with the "UID" and
- "SEQUENCE" properties to identify a specific instance of a
- recurring "VEVENT", "VTODO", or "VJOURNAL" calendar component.
- The property value is the original value of the "DTSTART" property
- of the recurrence instance.
-
-
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-
- Value Type: The default value type is DATE-TIME. The value type can
- be set to a DATE value type. This property MUST have the same
- value type as the "DTSTART" property contained within the
- recurring component. Furthermore, this property MUST be specified
- as a date with local time if and only if the "DTSTART" property
- contained within the recurring component is specified as a date
- with local time.
-
- Property Parameters: IANA, non-standard, value data type, time zone
- identifier, and recurrence identifier range parameters can be
- specified on this property.
-
- Conformance: This property can be specified in an iCalendar object
- containing a recurring calendar component.
-
- Description: The full range of calendar components specified by a
- recurrence set is referenced by referring to just the "UID"
- property value corresponding to the calendar component. The
- "RECURRENCE-ID" property allows the reference to an individual
- instance within the recurrence set.
-
- If the value of the "DTSTART" property is a DATE type value, then
- the value MUST be the calendar date for the recurrence instance.
-
- The DATE-TIME value is set to the time when the original
- recurrence instance would occur; meaning that if the intent is to
- change a Friday meeting to Thursday, the DATE-TIME is still set to
- the original Friday meeting.
-
- The "RECURRENCE-ID" property is used in conjunction with the "UID"
- and "SEQUENCE" properties to identify a particular instance of a
- recurring event, to-do, or journal. For a given pair of "UID" and
- "SEQUENCE" property values, the "RECURRENCE-ID" value for a
- recurrence instance is fixed.
-
- The "RANGE" parameter is used to specify the effective range of
- recurrence instances from the instance specified by the
- "RECURRENCE-ID" property value. The value for the range parameter
- can only be "THISANDFUTURE" to indicate a range defined by the
- given recurrence instance and all subsequent instances.
- Subsequent instances are determined by their "RECURRENCE-ID" value
- and not their current scheduled start time. Subsequent instances
- defined in separate components are not impacted by the given
- recurrence instance. When the given recurrence instance is
- rescheduled, all subsequent instances are also rescheduled by the
- same time difference. For instance, if the given recurrence
- instance is rescheduled to start 2 hours later, then all
- subsequent instances are also rescheduled 2 hours later.
-
-
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-
-
- Similarly, if the duration of the given recurrence instance is
- modified, then all subsequence instances are also modified to have
- this same duration.
-
- Note: The "RANGE" parameter may not be appropriate to
- reschedule specific subsequent instances of complex recurring
- calendar component. Assuming an unbounded recurring calendar
- component scheduled to occur on Mondays and Wednesdays, the
- "RANGE" parameter could not be used to reschedule only the
- future Monday instances to occur on Tuesday instead. In such
- cases, the calendar application could simply truncate the
- unbounded recurring calendar component (i.e., with the "COUNT"
- or "UNTIL" rule parts), and create two new unbounded recurring
- calendar components for the future instances.
-
- Format Definition: This property is defined by the following
- notation:
-
- recurid = "RECURRENCE-ID" ridparam ":" ridval CRLF
-
- ridparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
- (";" tzidparam) / (";" rangeparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- ridval = date-time / date
- ;Value MUST match value type
-
- Example: The following are examples of this property:
-
- RECURRENCE-ID;VALUE=DATE:19960401
-
- RECURRENCE-ID;RANGE=THISANDFUTURE:19960120T120000Z
-
-
-
-
-
-
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-
-
-3.8.4.5. Related To
-
- Property Name: RELATED-TO
-
- Purpose: This property is used to represent a relationship or
- reference between one calendar component and another.
-
- Value Type: TEXT
-
- Property Parameters: IANA, non-standard, and relationship type
- property parameters can be specified on this property.
-
- Conformance: This property can be specified in the "VEVENT",
- "VTODO", and "VJOURNAL" calendar components.
-
- Description: The property value consists of the persistent, globally
- unique identifier of another calendar component. This value would
- be represented in a calendar component by the "UID" property.
-
- By default, the property value points to another calendar
- component that has a PARENT relationship to the referencing
- object. The "RELTYPE" property parameter is used to either
- explicitly state the default PARENT relationship type to the
- referenced calendar component or to override the default PARENT
- relationship type and specify either a CHILD or SIBLING
- relationship. The PARENT relationship indicates that the calendar
- component is a subordinate of the referenced calendar component.
- The CHILD relationship indicates that the calendar component is a
- superior of the referenced calendar component. The SIBLING
- relationship indicates that the calendar component is a peer of
- the referenced calendar component.
-
- Changes to a calendar component referenced by this property can
- have an implicit impact on the related calendar component. For
- example, if a group event changes its start or end date or time,
- then the related, dependent events will need to have their start
- and end dates changed in a corresponding way. Similarly, if a
- PARENT calendar component is cancelled or deleted, then there is
- an implied impact to the related CHILD calendar components. This
- property is intended only to provide information on the
- relationship of calendar components. It is up to the target
- calendar system to maintain any property implications of this
- relationship.
-
-
-
-
-
-
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-
-
- Format Definition: This property is defined by the following
- notation:
-
- related = "RELATED-TO" relparam ":" text CRLF
-
- relparam = *(
- ;
- ; The following is OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" reltypeparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- The following is an example of this property:
-
- RELATED-TO:jsmith.part7.19960817T083000.xyzMail@example.com
-
- RELATED-TO:19960401-080045-4000F192713-0052@example.com
-
-3.8.4.6. Uniform Resource Locator
-
- Property Name: URL
-
- Purpose: This property defines a Uniform Resource Locator (URL)
- associated with the iCalendar object.
-
- Value Type: URI
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified once in the "VEVENT",
- "VTODO", "VJOURNAL", or "VFREEBUSY" calendar components.
-
- Description: This property may be used in a calendar component to
- convey a location where a more dynamic rendition of the calendar
- information associated with the calendar component can be found.
- This memo does not attempt to standardize the form of the URI, nor
- the format of the resource pointed to by the property value. If
- the URL property and Content-Location MIME header are both
- specified, they MUST point to the same resource.
-
-
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-
-
- Format Definition: This property is defined by the following
- notation:
-
- url = "URL" urlparam ":" uri CRLF
-
- urlparam = *(";" other-param)
-
- Example: The following is an example of this property:
-
- URL:http://example.com/pub/calendars/jsmith/mytime.ics
-
-3.8.4.7. Unique Identifier
-
- Property Name: UID
-
- Purpose: This property defines the persistent, globally unique
- identifier for the calendar component.
-
- Value Type: TEXT
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: The property MUST be specified in the "VEVENT",
- "VTODO", "VJOURNAL", or "VFREEBUSY" calendar components.
-
- Description: The "UID" itself MUST be a globally unique identifier.
- The generator of the identifier MUST guarantee that the identifier
- is unique. There are several algorithms that can be used to
- accomplish this. A good method to assure uniqueness is to put the
- domain name or a domain literal IP address of the host on which
- the identifier was created on the right-hand side of an "@", and
- on the left-hand side, put a combination of the current calendar
- date and time of day (i.e., formatted in as a DATE-TIME value)
- along with some other currently unique (perhaps sequential)
- identifier available on the system (for example, a process id
- number). Using a DATE-TIME value on the left-hand side and a
- domain name or domain literal on the right-hand side makes it
- possible to guarantee uniqueness since no two hosts should be
- using the same domain name or IP address at the same time. Though
- other algorithms will work, it is RECOMMENDED that the right-hand
- side contain some domain identifier (either of the host itself or
- otherwise) such that the generator of the message identifier can
- guarantee the uniqueness of the left-hand side within the scope of
- that domain.
-
- This is the method for correlating scheduling messages with the
- referenced "VEVENT", "VTODO", or "VJOURNAL" calendar component.
-
-
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-
-
- The full range of calendar components specified by a recurrence
- set is referenced by referring to just the "UID" property value
- corresponding to the calendar component. The "RECURRENCE-ID"
- property allows the reference to an individual instance within the
- recurrence set.
-
- This property is an important method for group-scheduling
- applications to match requests with later replies, modifications,
- or deletion requests. Calendaring and scheduling applications
- MUST generate this property in "VEVENT", "VTODO", and "VJOURNAL"
- calendar components to assure interoperability with other group-
- scheduling applications. This identifier is created by the
- calendar system that generates an iCalendar object.
-
- Implementations MUST be able to receive and persist values of at
- least 255 octets for this property, but they MUST NOT truncate
- values in the middle of a UTF-8 multi-octet sequence.
-
- Format Definition: This property is defined by the following
- notation:
-
- uid = "UID" uidparam ":" text CRLF
-
- uidparam = *(";" other-param)
-
- Example: The following is an example of this property:
-
- UID:19960401T080045Z-4000F192713-0052@example.com
-
-3.8.5. Recurrence Component Properties
-
- The following properties specify recurrence information in calendar
- components.
-
-3.8.5.1. Exception Date-Times
-
- Property Name: EXDATE
-
- Purpose: This property defines the list of DATE-TIME exceptions for
- recurring events, to-dos, journal entries, or time zone
- definitions.
-
- Value Type: The default value type for this property is DATE-TIME.
- The value type can be set to DATE.
-
- Property Parameters: IANA, non-standard, value data type, and time
- zone identifier property parameters can be specified on this
- property.
-
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-
- Conformance: This property can be specified in recurring "VEVENT",
- "VTODO", and "VJOURNAL" calendar components as well as in the
- "STANDARD" and "DAYLIGHT" sub-components of the "VTIMEZONE"
- calendar component.
-
- Description: The exception dates, if specified, are used in
- computing the recurrence set. The recurrence set is the complete
- set of recurrence instances for a calendar component. The
- recurrence set is generated by considering the initial "DTSTART"
- property along with the "RRULE", "RDATE", and "EXDATE" properties
- contained within the recurring component. The "DTSTART" property
- defines the first instance in the recurrence set. The "DTSTART"
- property value SHOULD match the pattern of the recurrence rule, if
- specified. The recurrence set generated with a "DTSTART" property
- value that doesn't match the pattern of the rule is undefined.
- The final recurrence set is generated by gathering all of the
- start DATE-TIME values generated by any of the specified "RRULE"
- and "RDATE" properties, and then excluding any start DATE-TIME
- values specified by "EXDATE" properties. This implies that start
- DATE-TIME values specified by "EXDATE" properties take precedence
- over those specified by inclusion properties (i.e., "RDATE" and
- "RRULE"). When duplicate instances are generated by the "RRULE"
- and "RDATE" properties, only one recurrence is considered.
- Duplicate instances are ignored.
-
- The "EXDATE" property can be used to exclude the value specified
- in "DTSTART". However, in such cases, the original "DTSTART" date
- MUST still be maintained by the calendaring and scheduling system
- because the original "DTSTART" value has inherent usage
- dependencies by other properties such as the "RECURRENCE-ID".
-
- Format Definition: This property is defined by the following
- notation:
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
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-
-
- exdate = "EXDATE" exdtparam ":" exdtval *("," exdtval) CRLF
-
- exdtparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
- ;
- (";" tzidparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- exdtval = date-time / date
- ;Value MUST match value type
-
- Example: The following is an example of this property:
-
- EXDATE:19960402T010000Z,19960403T010000Z,19960404T010000Z
-
-3.8.5.2. Recurrence Date-Times
-
- Property Name: RDATE
-
- Purpose: This property defines the list of DATE-TIME values for
- recurring events, to-dos, journal entries, or time zone
- definitions.
-
- Value Type: The default value type for this property is DATE-TIME.
- The value type can be set to DATE or PERIOD.
-
- Property Parameters: IANA, non-standard, value data type, and time
- zone identifier property parameters can be specified on this
- property.
-
- Conformance: This property can be specified in recurring "VEVENT",
- "VTODO", and "VJOURNAL" calendar components as well as in the
- "STANDARD" and "DAYLIGHT" sub-components of the "VTIMEZONE"
- calendar component.
-
- Description: This property can appear along with the "RRULE"
- property to define an aggregate set of repeating occurrences.
- When they both appear in a recurring component, the recurrence
-
-
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-
-
- instances are defined by the union of occurrences defined by both
- the "RDATE" and "RRULE".
-
- The recurrence dates, if specified, are used in computing the
- recurrence set. The recurrence set is the complete set of
- recurrence instances for a calendar component. The recurrence set
- is generated by considering the initial "DTSTART" property along
- with the "RRULE", "RDATE", and "EXDATE" properties contained
- within the recurring component. The "DTSTART" property defines
- the first instance in the recurrence set. The "DTSTART" property
- value SHOULD match the pattern of the recurrence rule, if
- specified. The recurrence set generated with a "DTSTART" property
- value that doesn't match the pattern of the rule is undefined.
- The final recurrence set is generated by gathering all of the
- start DATE-TIME values generated by any of the specified "RRULE"
- and "RDATE" properties, and then excluding any start DATE-TIME
- values specified by "EXDATE" properties. This implies that start
- DATE-TIME values specified by "EXDATE" properties take precedence
- over those specified by inclusion properties (i.e., "RDATE" and
- "RRULE"). Where duplicate instances are generated by the "RRULE"
- and "RDATE" properties, only one recurrence is considered.
- Duplicate instances are ignored.
-
- Format Definition: This property is defined by the following
- notation:
-
- rdate = "RDATE" rdtparam ":" rdtval *("," rdtval) CRLF
-
- rdtparam = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" "VALUE" "=" ("DATE-TIME" / "DATE" / "PERIOD")) /
- (";" tzidparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- rdtval = date-time / date / period
- ;Value MUST match value type
-
-
-
-
-
-
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-
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-
-
- Example: The following are examples of this property:
-
- RDATE:19970714T123000Z
- RDATE;TZID=America/New_York:19970714T083000
-
- RDATE;VALUE=PERIOD:19960403T020000Z/19960403T040000Z,
- 19960404T010000Z/PT3H
-
- RDATE;VALUE=DATE:19970101,19970120,19970217,19970421
- 19970526,19970704,19970901,19971014,19971128,19971129,19971225
-
-3.8.5.3. Recurrence Rule
-
- Property Name: RRULE
-
- Purpose: This property defines a rule or repeating pattern for
- recurring events, to-dos, journal entries, or time zone
- definitions.
-
- Value Type: RECUR
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified in recurring "VEVENT",
- "VTODO", and "VJOURNAL" calendar components as well as in the
- "STANDARD" and "DAYLIGHT" sub-components of the "VTIMEZONE"
- calendar component, but it SHOULD NOT be specified more than once.
- The recurrence set generated with multiple "RRULE" properties is
- undefined.
-
- Description: The recurrence rule, if specified, is used in computing
- the recurrence set. The recurrence set is the complete set of
- recurrence instances for a calendar component. The recurrence set
- is generated by considering the initial "DTSTART" property along
- with the "RRULE", "RDATE", and "EXDATE" properties contained
- within the recurring component. The "DTSTART" property defines
- the first instance in the recurrence set. The "DTSTART" property
- value SHOULD be synchronized with the recurrence rule, if
- specified. The recurrence set generated with a "DTSTART" property
- value not synchronized with the recurrence rule is undefined. The
- final recurrence set is generated by gathering all of the start
- DATE-TIME values generated by any of the specified "RRULE" and
- "RDATE" properties, and then excluding any start DATE-TIME values
- specified by "EXDATE" properties. This implies that start DATE-
- TIME values specified by "EXDATE" properties take precedence over
- those specified by inclusion properties (i.e., "RDATE" and
- "RRULE"). Where duplicate instances are generated by the "RRULE"
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- and "RDATE" properties, only one recurrence is considered.
- Duplicate instances are ignored.
-
- The "DTSTART" property specified within the iCalendar object
- defines the first instance of the recurrence. In most cases, a
- "DTSTART" property of DATE-TIME value type used with a recurrence
- rule, should be specified as a date with local time and time zone
- reference to make sure all the recurrence instances start at the
- same local time regardless of time zone changes.
-
- If the duration of the recurring component is specified with the
- "DTEND" or "DUE" property, then the same exact duration will apply
- to all the members of the generated recurrence set. Else, if the
- duration of the recurring component is specified with the
- "DURATION" property, then the same nominal duration will apply to
- all the members of the generated recurrence set and the exact
- duration of each recurrence instance will depend on its specific
- start time. For example, recurrence instances of a nominal
- duration of one day will have an exact duration of more or less
- than 24 hours on a day where a time zone shift occurs. The
- duration of a specific recurrence may be modified in an exception
- component or simply by using an "RDATE" property of PERIOD value
- type.
-
- Format Definition: This property is defined by the following
- notation:
-
- rrule = "RRULE" rrulparam ":" recur CRLF
-
- rrulparam = *(";" other-param)
-
- Example: All examples assume the Eastern United States time zone.
-
- Daily for 10 occurrences:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=DAILY;COUNT=10
-
- ==> (1997 9:00 AM EDT) September 2-11
-
- Daily until December 24, 1997:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=DAILY;UNTIL=19971224T000000Z
-
- ==> (1997 9:00 AM EDT) September 2-30;October 1-25
- (1997 9:00 AM EST) October 26-31;November 1-30;December 1-23
-
-
-
-
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-
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-
-
- Every other day - forever:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=DAILY;INTERVAL=2
-
- ==> (1997 9:00 AM EDT) September 2,4,6,8...24,26,28,30;
- October 2,4,6...20,22,24
- (1997 9:00 AM EST) October 26,28,30;
- November 1,3,5,7...25,27,29;
- December 1,3,...
-
- Every 10 days, 5 occurrences:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=DAILY;INTERVAL=10;COUNT=5
-
- ==> (1997 9:00 AM EDT) September 2,12,22;
- October 2,12
-
- Every day in January, for 3 years:
-
- DTSTART;TZID=America/New_York:19980101T090000
-
- RRULE:FREQ=YEARLY;UNTIL=20000131T140000Z;
- BYMONTH=1;BYDAY=SU,MO,TU,WE,TH,FR,SA
- or
- RRULE:FREQ=DAILY;UNTIL=20000131T140000Z;BYMONTH=1
-
- ==> (1998 9:00 AM EST)January 1-31
- (1999 9:00 AM EST)January 1-31
- (2000 9:00 AM EST)January 1-31
-
- Weekly for 10 occurrences:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=WEEKLY;COUNT=10
-
- ==> (1997 9:00 AM EDT) September 2,9,16,23,30;October 7,14,21
- (1997 9:00 AM EST) October 28;November 4
-
-
-
-
-
-
-
-
-
-
-
-
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-
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-
-
- Weekly until December 24, 1997:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=WEEKLY;UNTIL=19971224T000000Z
-
- ==> (1997 9:00 AM EDT) September 2,9,16,23,30;
- October 7,14,21
- (1997 9:00 AM EST) October 28;
- November 4,11,18,25;
- December 2,9,16,23
-
- Every other week - forever:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=WEEKLY;INTERVAL=2;WKST=SU
-
- ==> (1997 9:00 AM EDT) September 2,16,30;
- October 14
- (1997 9:00 AM EST) October 28;
- November 11,25;
- December 9,23
- (1998 9:00 AM EST) January 6,20;
- February 3, 17
- ...
-
- Weekly on Tuesday and Thursday for five weeks:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=WEEKLY;UNTIL=19971007T000000Z;WKST=SU;BYDAY=TU,TH
-
- or
-
- RRULE:FREQ=WEEKLY;COUNT=10;WKST=SU;BYDAY=TU,TH
-
- ==> (1997 9:00 AM EDT) September 2,4,9,11,16,18,23,25,30;
- October 2
-
- Every other week on Monday, Wednesday, and Friday until December
- 24, 1997, starting on Monday, September 1, 1997:
-
- DTSTART;TZID=America/New_York:19970901T090000
- RRULE:FREQ=WEEKLY;INTERVAL=2;UNTIL=19971224T000000Z;WKST=SU;
- BYDAY=MO,WE,FR
-
- ==> (1997 9:00 AM EDT) September 1,3,5,15,17,19,29;
- October 1,3,13,15,17
- (1997 9:00 AM EST) October 27,29,31;
- November 10,12,14,24,26,28;
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- December 8,10,12,22
-
- Every other week on Tuesday and Thursday, for 8 occurrences:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=WEEKLY;INTERVAL=2;COUNT=8;WKST=SU;BYDAY=TU,TH
-
- ==> (1997 9:00 AM EDT) September 2,4,16,18,30;
- October 2,14,16
-
- Monthly on the first Friday for 10 occurrences:
-
- DTSTART;TZID=America/New_York:19970905T090000
- RRULE:FREQ=MONTHLY;COUNT=10;BYDAY=1FR
-
- ==> (1997 9:00 AM EDT) September 5;October 3
- (1997 9:00 AM EST) November 7;December 5
- (1998 9:00 AM EST) January 2;February 6;March 6;April 3
- (1998 9:00 AM EDT) May 1;June 5
-
- Monthly on the first Friday until December 24, 1997:
-
- DTSTART;TZID=America/New_York:19970905T090000
- RRULE:FREQ=MONTHLY;UNTIL=19971224T000000Z;BYDAY=1FR
-
- ==> (1997 9:00 AM EDT) September 5; October 3
- (1997 9:00 AM EST) November 7; December 5
-
- Every other month on the first and last Sunday of the month for 10
- occurrences:
-
- DTSTART;TZID=America/New_York:19970907T090000
- RRULE:FREQ=MONTHLY;INTERVAL=2;COUNT=10;BYDAY=1SU,-1SU
-
- ==> (1997 9:00 AM EDT) September 7,28
- (1997 9:00 AM EST) November 2,30
- (1998 9:00 AM EST) January 4,25;March 1,29
- (1998 9:00 AM EDT) May 3,31
-
- Monthly on the second-to-last Monday of the month for 6 months:
-
- DTSTART;TZID=America/New_York:19970922T090000
- RRULE:FREQ=MONTHLY;COUNT=6;BYDAY=-2MO
-
- ==> (1997 9:00 AM EDT) September 22;October 20
- (1997 9:00 AM EST) November 17;December 22
- (1998 9:00 AM EST) January 19;February 16
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Monthly on the third-to-the-last day of the month, forever:
-
- DTSTART;TZID=America/New_York:19970928T090000
- RRULE:FREQ=MONTHLY;BYMONTHDAY=-3
-
- ==> (1997 9:00 AM EDT) September 28
- (1997 9:00 AM EST) October 29;November 28;December 29
- (1998 9:00 AM EST) January 29;February 26
- ...
-
- Monthly on the 2nd and 15th of the month for 10 occurrences:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=MONTHLY;COUNT=10;BYMONTHDAY=2,15
-
- ==> (1997 9:00 AM EDT) September 2,15;October 2,15
- (1997 9:00 AM EST) November 2,15;December 2,15
- (1998 9:00 AM EST) January 2,15
-
- Monthly on the first and last day of the month for 10 occurrences:
-
- DTSTART;TZID=America/New_York:19970930T090000
- RRULE:FREQ=MONTHLY;COUNT=10;BYMONTHDAY=1,-1
-
- ==> (1997 9:00 AM EDT) September 30;October 1
- (1997 9:00 AM EST) October 31;November 1,30;December 1,31
- (1998 9:00 AM EST) January 1,31;February 1
-
- Every 18 months on the 10th thru 15th of the month for 10
- occurrences:
-
- DTSTART;TZID=America/New_York:19970910T090000
- RRULE:FREQ=MONTHLY;INTERVAL=18;COUNT=10;BYMONTHDAY=10,11,12,
- 13,14,15
-
- ==> (1997 9:00 AM EDT) September 10,11,12,13,14,15
- (1999 9:00 AM EST) March 10,11,12,13
-
- Every Tuesday, every other month:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=MONTHLY;INTERVAL=2;BYDAY=TU
-
- ==> (1997 9:00 AM EDT) September 2,9,16,23,30
- (1997 9:00 AM EST) November 4,11,18,25
- (1998 9:00 AM EST) January 6,13,20,27;March 3,10,17,24,31
- ...
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Yearly in June and July for 10 occurrences:
-
- DTSTART;TZID=America/New_York:19970610T090000
- RRULE:FREQ=YEARLY;COUNT=10;BYMONTH=6,7
-
- ==> (1997 9:00 AM EDT) June 10;July 10
- (1998 9:00 AM EDT) June 10;July 10
- (1999 9:00 AM EDT) June 10;July 10
- (2000 9:00 AM EDT) June 10;July 10
- (2001 9:00 AM EDT) June 10;July 10
-
- Note: Since none of the BYDAY, BYMONTHDAY, or BYYEARDAY
- components are specified, the day is gotten from "DTSTART".
-
- Every other year on January, February, and March for 10
- occurrences:
-
- DTSTART;TZID=America/New_York:19970310T090000
- RRULE:FREQ=YEARLY;INTERVAL=2;COUNT=10;BYMONTH=1,2,3
-
- ==> (1997 9:00 AM EST) March 10
- (1999 9:00 AM EST) January 10;February 10;March 10
- (2001 9:00 AM EST) January 10;February 10;March 10
- (2003 9:00 AM EST) January 10;February 10;March 10
-
- Every third year on the 1st, 100th, and 200th day for 10
- occurrences:
-
- DTSTART;TZID=America/New_York:19970101T090000
- RRULE:FREQ=YEARLY;INTERVAL=3;COUNT=10;BYYEARDAY=1,100,200
-
- ==> (1997 9:00 AM EST) January 1
- (1997 9:00 AM EDT) April 10;July 19
- (2000 9:00 AM EST) January 1
- (2000 9:00 AM EDT) April 9;July 18
- (2003 9:00 AM EST) January 1
- (2003 9:00 AM EDT) April 10;July 19
- (2006 9:00 AM EST) January 1
-
- Every 20th Monday of the year, forever:
-
- DTSTART;TZID=America/New_York:19970519T090000
- RRULE:FREQ=YEARLY;BYDAY=20MO
-
- ==> (1997 9:00 AM EDT) May 19
- (1998 9:00 AM EDT) May 18
- (1999 9:00 AM EDT) May 17
- ...
-
-
-
-Desruisseaux Standards Track [Page 128]
-
-RFC 5545 iCalendar September 2009
-
-
- Monday of week number 20 (where the default start of the week is
- Monday), forever:
-
- DTSTART;TZID=America/New_York:19970512T090000
- RRULE:FREQ=YEARLY;BYWEEKNO=20;BYDAY=MO
-
- ==> (1997 9:00 AM EDT) May 12
- (1998 9:00 AM EDT) May 11
- (1999 9:00 AM EDT) May 17
- ...
-
- Every Thursday in March, forever:
-
- DTSTART;TZID=America/New_York:19970313T090000
- RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=TH
-
- ==> (1997 9:00 AM EST) March 13,20,27
- (1998 9:00 AM EST) March 5,12,19,26
- (1999 9:00 AM EST) March 4,11,18,25
- ...
-
- Every Thursday, but only during June, July, and August, forever:
-
- DTSTART;TZID=America/New_York:19970605T090000
- RRULE:FREQ=YEARLY;BYDAY=TH;BYMONTH=6,7,8
-
- ==> (1997 9:00 AM EDT) June 5,12,19,26;July 3,10,17,24,31;
- August 7,14,21,28
- (1998 9:00 AM EDT) June 4,11,18,25;July 2,9,16,23,30;
- August 6,13,20,27
- (1999 9:00 AM EDT) June 3,10,17,24;July 1,8,15,22,29;
- August 5,12,19,26
- ...
-
- Every Friday the 13th, forever:
-
- DTSTART;TZID=America/New_York:19970902T090000
- EXDATE;TZID=America/New_York:19970902T090000
- RRULE:FREQ=MONTHLY;BYDAY=FR;BYMONTHDAY=13
-
- ==> (1998 9:00 AM EST) February 13;March 13;November 13
- (1999 9:00 AM EDT) August 13
- (2000 9:00 AM EDT) October 13
- ...
-
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- The first Saturday that follows the first Sunday of the month,
- forever:
-
- DTSTART;TZID=America/New_York:19970913T090000
- RRULE:FREQ=MONTHLY;BYDAY=SA;BYMONTHDAY=7,8,9,10,11,12,13
-
- ==> (1997 9:00 AM EDT) September 13;October 11
- (1997 9:00 AM EST) November 8;December 13
- (1998 9:00 AM EST) January 10;February 7;March 7
- (1998 9:00 AM EDT) April 11;May 9;June 13...
- ...
-
- Every 4 years, the first Tuesday after a Monday in November,
- forever (U.S. Presidential Election day):
-
- DTSTART;TZID=America/New_York:19961105T090000
- RRULE:FREQ=YEARLY;INTERVAL=4;BYMONTH=11;BYDAY=TU;
- BYMONTHDAY=2,3,4,5,6,7,8
-
- ==> (1996 9:00 AM EST) November 5
- (2000 9:00 AM EST) November 7
- (2004 9:00 AM EST) November 2
- ...
-
- The third instance into the month of one of Tuesday, Wednesday, or
- Thursday, for the next 3 months:
-
- DTSTART;TZID=America/New_York:19970904T090000
- RRULE:FREQ=MONTHLY;COUNT=3;BYDAY=TU,WE,TH;BYSETPOS=3
-
- ==> (1997 9:00 AM EDT) September 4;October 7
- (1997 9:00 AM EST) November 6
-
- The second-to-last weekday of the month:
-
- DTSTART;TZID=America/New_York:19970929T090000
- RRULE:FREQ=MONTHLY;BYDAY=MO,TU,WE,TH,FR;BYSETPOS=-2
-
- ==> (1997 9:00 AM EDT) September 29
- (1997 9:00 AM EST) October 30;November 27;December 30
- (1998 9:00 AM EST) January 29;February 26;March 30
- ...
-
-
-
-
-
-
-
-
-
-Desruisseaux Standards Track [Page 130]
-
-RFC 5545 iCalendar September 2009
-
-
- Every 3 hours from 9:00 AM to 5:00 PM on a specific day:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=HOURLY;INTERVAL=3;UNTIL=19970902T170000Z
-
- ==> (September 2, 1997 EDT) 09:00,12:00,15:00
-
- Every 15 minutes for 6 occurrences:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=MINUTELY;INTERVAL=15;COUNT=6
-
- ==> (September 2, 1997 EDT) 09:00,09:15,09:30,09:45,10:00,10:15
-
- Every hour and a half for 4 occurrences:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=MINUTELY;INTERVAL=90;COUNT=4
-
- ==> (September 2, 1997 EDT) 09:00,10:30;12:00;13:30
-
- Every 20 minutes from 9:00 AM to 4:40 PM every day:
-
- DTSTART;TZID=America/New_York:19970902T090000
- RRULE:FREQ=DAILY;BYHOUR=9,10,11,12,13,14,15,16;BYMINUTE=0,20,40
- or
- RRULE:FREQ=MINUTELY;INTERVAL=20;BYHOUR=9,10,11,12,13,14,15,16
-
- ==> (September 2, 1997 EDT) 9:00,9:20,9:40,10:00,10:20,
- ... 16:00,16:20,16:40
- (September 3, 1997 EDT) 9:00,9:20,9:40,10:00,10:20,
- ...16:00,16:20,16:40
- ...
-
- An example where the days generated makes a difference because of
- WKST:
-
- DTSTART;TZID=America/New_York:19970805T090000
- RRULE:FREQ=WEEKLY;INTERVAL=2;COUNT=4;BYDAY=TU,SU;WKST=MO
-
- ==> (1997 EDT) August 5,10,19,24
-
- changing only WKST from MO to SU, yields different results...
-
- DTSTART;TZID=America/New_York:19970805T090000
- RRULE:FREQ=WEEKLY;INTERVAL=2;COUNT=4;BYDAY=TU,SU;WKST=SU
-
- ==> (1997 EDT) August 5,17,19,31
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- An example where an invalid date (i.e., February 30) is ignored.
-
- DTSTART;TZID=America/New_York:20070115T090000
- RRULE:FREQ=MONTHLY;BYMONTHDAY=15,30;COUNT=5
-
- ==> (2007 EST) January 15,30
- (2007 EST) February 15
- (2007 EDT) March 15,30
-
-3.8.6. Alarm Component Properties
-
- The following properties specify alarm information in calendar
- components.
-
-3.8.6.1. Action
-
- Property Name: ACTION
-
- Purpose: This property defines the action to be invoked when an
- alarm is triggered.
-
- Value Type: TEXT
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property MUST be specified once in a "VALARM"
- calendar component.
-
- Description: Each "VALARM" calendar component has a particular type
- of action with which it is associated. This property specifies
- the type of action. Applications MUST ignore alarms with x-name
- and iana-token values they don't recognize.
-
- Format Definition: This property is defined by the following
- notation:
-
- action = "ACTION" actionparam ":" actionvalue CRLF
-
- actionparam = *(";" other-param)
-
-
- actionvalue = "AUDIO" / "DISPLAY" / "EMAIL"
- / iana-token / x-name
-
- Example: The following are examples of this property in a "VALARM"
- calendar component:
-
-
-
-
-Desruisseaux Standards Track [Page 132]
-
-RFC 5545 iCalendar September 2009
-
-
- ACTION:AUDIO
-
- ACTION:DISPLAY
-
-3.8.6.2. Repeat Count
-
- Property Name: REPEAT
-
- Purpose: This property defines the number of times the alarm should
- be repeated, after the initial trigger.
-
- Value Type: INTEGER
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified in a "VALARM" calendar
- component.
-
- Description: This property defines the number of times an alarm
- should be repeated after its initial trigger. If the alarm
- triggers more than once, then this property MUST be specified
- along with the "DURATION" property.
-
- Format Definition: This property is defined by the following
- notation:
-
- repeat = "REPEAT" repparam ":" integer CRLF
- ;Default is "0", zero.
-
- repparam = *(";" other-param)
-
- Example: The following is an example of this property for an alarm
- that repeats 4 additional times with a 5-minute delay after the
- initial triggering of the alarm:
-
- REPEAT:4
- DURATION:PT5M
-
-3.8.6.3. Trigger
-
- Property Name: TRIGGER
-
- Purpose: This property specifies when an alarm will trigger.
-
- Value Type: The default value type is DURATION. The value type can
- be set to a DATE-TIME value type, in which case the value MUST
- specify a UTC-formatted DATE-TIME value.
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Property Parameters: IANA, non-standard, value data type, time zone
- identifier, or trigger relationship property parameters can be
- specified on this property. The trigger relationship property
- parameter MUST only be specified when the value type is
- "DURATION".
-
- Conformance: This property MUST be specified in the "VALARM"
- calendar component.
-
- Description: This property defines when an alarm will trigger. The
- default value type is DURATION, specifying a relative time for the
- trigger of the alarm. The default duration is relative to the
- start of an event or to-do with which the alarm is associated.
- The duration can be explicitly set to trigger from either the end
- or the start of the associated event or to-do with the "RELATED"
- parameter. A value of START will set the alarm to trigger off the
- start of the associated event or to-do. A value of END will set
- the alarm to trigger off the end of the associated event or to-do.
-
- Either a positive or negative duration may be specified for the
- "TRIGGER" property. An alarm with a positive duration is
- triggered after the associated start or end of the event or to-do.
- An alarm with a negative duration is triggered before the
- associated start or end of the event or to-do.
-
- The "RELATED" property parameter is not valid if the value type of
- the property is set to DATE-TIME (i.e., for an absolute date and
- time alarm trigger). If a value type of DATE-TIME is specified,
- then the property value MUST be specified in the UTC time format.
- If an absolute trigger is specified on an alarm for a recurring
- event or to-do, then the alarm will only trigger for the specified
- absolute DATE-TIME, along with any specified repeating instances.
-
- If the trigger is set relative to START, then the "DTSTART"
- property MUST be present in the associated "VEVENT" or "VTODO"
- calendar component. If an alarm is specified for an event with
- the trigger set relative to the END, then the "DTEND" property or
- the "DTSTART" and "DURATION " properties MUST be present in the
- associated "VEVENT" calendar component. If the alarm is specified
- for a to-do with a trigger set relative to the END, then either
- the "DUE" property or the "DTSTART" and "DURATION " properties
- MUST be present in the associated "VTODO" calendar component.
-
- Alarms specified in an event or to-do that is defined in terms of
- a DATE value type will be triggered relative to 00:00:00 of the
- user's configured time zone on the specified date, or relative to
- 00:00:00 UTC on the specified date if no configured time zone can
- be found for the user. For example, if "DTSTART" is a DATE value
-
-
-
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-
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-
-
- set to 19980205 then the duration trigger will be relative to
- 19980205T000000 America/New_York for a user configured with the
- America/New_York time zone.
-
- Format Definition: This property is defined by the following
- notation:
-
- trigger = "TRIGGER" (trigrel / trigabs) CRLF
-
- trigrel = *(
- ;
- ; The following are OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" "VALUE" "=" "DURATION") /
- (";" trigrelparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- ) ":" dur-value
-
- trigabs = *(
- ;
- ; The following is REQUIRED,
- ; but MUST NOT occur more than once.
- ;
- (";" "VALUE" "=" "DATE-TIME") /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- ) ":" date-time
-
- Example: A trigger set 15 minutes prior to the start of the event or
- to-do.
-
- TRIGGER:-PT15M
-
- A trigger set five minutes after the end of an event or the due
- date of a to-do.
-
- TRIGGER;RELATED=END:PT5M
-
-
-
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-
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-
-
- A trigger set to an absolute DATE-TIME.
-
- TRIGGER;VALUE=DATE-TIME:19980101T050000Z
-
-3.8.7. Change Management Component Properties
-
- The following properties specify change management information in
- calendar components.
-
-3.8.7.1. Date-Time Created
-
- Property Name: CREATED
-
- Purpose: This property specifies the date and time that the calendar
- information was created by the calendar user agent in the calendar
- store.
-
- Note: This is analogous to the creation date and time for a
- file in the file system.
-
- Value Type: DATE-TIME
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: The property can be specified once in "VEVENT",
- "VTODO", or "VJOURNAL" calendar components. The value MUST be
- specified as a date with UTC time.
-
- Description: This property specifies the date and time that the
- calendar information was created by the calendar user agent in the
- calendar store.
-
- Format Definition: This property is defined by the following
- notation:
-
- created = "CREATED" creaparam ":" date-time CRLF
-
- creaparam = *(";" other-param)
-
- Example: The following is an example of this property:
-
- CREATED:19960329T133000Z
-
-
-
-
-
-
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-
-
-3.8.7.2. Date-Time Stamp
-
- Property Name: DTSTAMP
-
- Purpose: In the case of an iCalendar object that specifies a
- "METHOD" property, this property specifies the date and time that
- the instance of the iCalendar object was created. In the case of
- an iCalendar object that doesn't specify a "METHOD" property, this
- property specifies the date and time that the information
- associated with the calendar component was last revised in the
- calendar store.
-
- Value Type: DATE-TIME
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property MUST be included in the "VEVENT",
- "VTODO", "VJOURNAL", or "VFREEBUSY" calendar components.
-
- Description: The value MUST be specified in the UTC time format.
-
- This property is also useful to protocols such as [2447bis] that
- have inherent latency issues with the delivery of content. This
- property will assist in the proper sequencing of messages
- containing iCalendar objects.
-
- In the case of an iCalendar object that specifies a "METHOD"
- property, this property differs from the "CREATED" and "LAST-
- MODIFIED" properties. These two properties are used to specify
- when the particular calendar data in the calendar store was
- created and last modified. This is different than when the
- iCalendar object representation of the calendar service
- information was created or last modified.
-
- In the case of an iCalendar object that doesn't specify a "METHOD"
- property, this property is equivalent to the "LAST-MODIFIED"
- property.
-
- Format Definition: This property is defined by the following
- notation:
-
- dtstamp = "DTSTAMP" stmparam ":" date-time CRLF
-
- stmparam = *(";" other-param)
-
-
-
-
-
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-
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-
-
- Example:
-
- DTSTAMP:19971210T080000Z
-
-3.8.7.3. Last Modified
-
- Property Name: LAST-MODIFIED
-
- Purpose: This property specifies the date and time that the
- information associated with the calendar component was last
- revised in the calendar store.
-
- Note: This is analogous to the modification date and time for a
- file in the file system.
-
- Value Type: DATE-TIME
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
- Conformance: This property can be specified in the "VEVENT",
- "VTODO", "VJOURNAL", or "VTIMEZONE" calendar components.
-
- Description: The property value MUST be specified in the UTC time
- format.
-
- Format Definition: This property is defined by the following
- notation:
-
- last-mod = "LAST-MODIFIED" lstparam ":" date-time CRLF
-
- lstparam = *(";" other-param)
-
- Example: The following is an example of this property:
-
- LAST-MODIFIED:19960817T133000Z
-
-3.8.7.4. Sequence Number
-
- Property Name: SEQUENCE
-
- Purpose: This property defines the revision sequence number of the
- calendar component within a sequence of revisions.
-
- Value Type: INTEGER
-
- Property Parameters: IANA and non-standard property parameters can
- be specified on this property.
-
-
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-
-
- Conformance: The property can be specified in "VEVENT", "VTODO", or
- "VJOURNAL" calendar component.
-
- Description: When a calendar component is created, its sequence
- number is 0. It is monotonically incremented by the "Organizer's"
- CUA each time the "Organizer" makes a significant revision to the
- calendar component.
-
- The "Organizer" includes this property in an iCalendar object that
- it sends to an "Attendee" to specify the current version of the
- calendar component.
-
- The "Attendee" includes this property in an iCalendar object that
- it sends to the "Organizer" to specify the version of the calendar
- component to which the "Attendee" is referring.
-
- A change to the sequence number is not the mechanism that an
- "Organizer" uses to request a response from the "Attendees". The
- "RSVP" parameter on the "ATTENDEE" property is used by the
- "Organizer" to indicate that a response from the "Attendees" is
- requested.
-
- Recurrence instances of a recurring component MAY have different
- sequence numbers.
-
- Format Definition: This property is defined by the following
- notation:
-
- seq = "SEQUENCE" seqparam ":" integer CRLF
- ; Default is "0"
-
- seqparam = *(";" other-param)
-
- Example: The following is an example of this property for a calendar
- component that was just created by the "Organizer":
-
- SEQUENCE:0
-
- The following is an example of this property for a calendar
- component that has been revised two different times by the
- "Organizer":
-
- SEQUENCE:2
-
-3.8.8. Miscellaneous Component Properties
-
- The following properties specify information about a number of
- miscellaneous features of calendar components.
-
-
-
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-
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-
-
-3.8.8.1. IANA Properties
-
- Property Name: An IANA-registered property name
-
- Value Type: The default value type is TEXT. The value type can be
- set to any value type.
-
- Property Parameters: Any parameter can be specified on this
- property.
-
- Description: This specification allows other properties registered
- with IANA to be specified in any calendar components. Compliant
- applications are expected to be able to parse these other IANA-
- registered properties but can ignore them.
-
- Format Definition: This property is defined by the following
- notation:
-
- iana-prop = iana-token *(";" icalparameter) ":" value CRLF
-
- Example: The following are examples of properties that might be
- registered to IANA:
-
- DRESSCODE:CASUAL
-
- NON-SMOKING;VALUE=BOOLEAN:TRUE
-
-3.8.8.2. Non-Standard Properties
-
- Property Name: Any property name with a "X-" prefix
-
- Purpose: This class of property provides a framework for defining
- non-standard properties.
-
- Value Type: The default value type is TEXT. The value type can be
- set to any value type.
-
- Property Parameters: IANA, non-standard, and language property
- parameters can be specified on this property.
-
- Conformance: This property can be specified in any calendar
- component.
-
- Description: The MIME Calendaring and Scheduling Content Type
- provides a "standard mechanism for doing non-standard things".
- This extension support is provided for implementers to "push the
- envelope" on the existing version of the memo. Extension
- properties are specified by property and/or property parameter
-
-
-
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-
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-
-
- names that have the prefix text of "X-" (the two-character
- sequence: LATIN CAPITAL LETTER X character followed by the HYPHEN-
- MINUS character). It is recommended that vendors concatenate onto
- this sentinel another short prefix text to identify the vendor.
- This will facilitate readability of the extensions and minimize
- possible collision of names between different vendors. User
- agents that support this content type are expected to be able to
- parse the extension properties and property parameters but can
- ignore them.
-
- At present, there is no registration authority for names of
- extension properties and property parameters. The value type for
- this property is TEXT. Optionally, the value type can be any of
- the other valid value types.
-
- Format Definition: This property is defined by the following
- notation:
-
- x-prop = x-name *(";" icalparameter) ":" value CRLF
-
- Example: The following might be the ABC vendor's extension for an
- audio-clip form of subject property:
-
- X-ABC-MMSUBJ;VALUE=URI;FMTTYPE=audio/basic:http://www.example.
- org/mysubj.au
-
-3.8.8.3. Request Status
-
- Property Name: REQUEST-STATUS
-
- Purpose: This property defines the status code returned for a
- scheduling request.
-
- Value Type: TEXT
-
- Property Parameters: IANA, non-standard, and language property
- parameters can be specified on this property.
-
- Conformance: The property can be specified in the "VEVENT", "VTODO",
- "VJOURNAL", or "VFREEBUSY" calendar component.
-
- Description: This property is used to return status code information
- related to the processing of an associated iCalendar object. The
- value type for this property is TEXT.
-
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- The value consists of a short return status component, a longer
- return status description component, and optionally a status-
- specific data component. The components of the value are
- separated by the SEMICOLON character.
-
- The short return status is a PERIOD character separated pair or
- 3-tuple of integers. For example, "3.1" or "3.1.1". The
- successive levels of integers provide for a successive level of
- status code granularity.
-
- The following are initial classes for the return status code.
- Individual iCalendar object methods will define specific return
- status codes for these classes. In addition, other classes for
- the return status code may be defined using the registration
- process defined later in this memo.
-
- +--------+----------------------------------------------------------+
- | Short | Longer Return Status Description |
- | Return | |
- | Status | |
- | Code | |
- +--------+----------------------------------------------------------+
- | 1.xx | Preliminary success. This class of status code |
- | | indicates that the request has been initially processed |
- | | but that completion is pending. |
- | | |
- | 2.xx | Successful. This class of status code indicates that |
- | | the request was completed successfully. However, the |
- | | exact status code can indicate that a fallback has been |
- | | taken. |
- | | |
- | 3.xx | Client Error. This class of status code indicates that |
- | | the request was not successful. The error is the result |
- | | of either a syntax or a semantic error in the client- |
- | | formatted request. Request should not be retried until |
- | | the condition in the request is corrected. |
- | | |
- | 4.xx | Scheduling Error. This class of status code indicates |
- | | that the request was not successful. Some sort of error |
- | | occurred within the calendaring and scheduling service, |
- | | not directly related to the request itself. |
- +--------+----------------------------------------------------------+
-
-
-
-
-
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Format Definition: This property is defined by the following
- notation:
-
- rstatus = "REQUEST-STATUS" rstatparam ":"
- statcode ";" statdesc [";" extdata]
-
- rstatparam = *(
- ;
- ; The following is OPTIONAL,
- ; but MUST NOT occur more than once.
- ;
- (";" languageparam) /
- ;
- ; The following is OPTIONAL,
- ; and MAY occur more than once.
- ;
- (";" other-param)
- ;
- )
-
- statcode = 1*DIGIT 1*2("." 1*DIGIT)
- ;Hierarchical, numeric return status code
-
- statdesc = text
- ;Textual status description
-
- extdata = text
- ;Textual exception data. For example, the offending property
- ;name and value or complete property line.
-
- Example: The following are some possible examples of this property.
-
- The COMMA and SEMICOLON separator characters in the property value
- are BACKSLASH character escaped because they appear in a text
- value.
-
- REQUEST-STATUS:2.0;Success
-
- REQUEST-STATUS:3.1;Invalid property value;DTSTART:96-Apr-01
-
- REQUEST-STATUS:2.8; Success\, repeating event ignored. Scheduled
- as a single event.;RRULE:FREQ=WEEKLY\;INTERVAL=2
-
- REQUEST-STATUS:4.1;Event conflict. Date-time is busy.
-
- REQUEST-STATUS:3.7;Invalid calendar user;ATTENDEE:
- mailto:jsmith@example.com
-
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
-4. iCalendar Object Examples
-
- The following examples are provided as an informational source of
- illustrative iCalendar objects consistent with this content type.
-
- The following example specifies a three-day conference that begins at
- 2:30 P.M. UTC, September 18, 1996 and ends at 10:00 P.M. UTC,
- September 20, 1996.
-
- BEGIN:VCALENDAR
- PRODID:-//xyz Corp//NONSGML PDA Calendar Version 1.0//EN
- VERSION:2.0
- BEGIN:VEVENT
- DTSTAMP:19960704T120000Z
- UID:uid1@example.com
- ORGANIZER:mailto:jsmith@example.com
- DTSTART:19960918T143000Z
- DTEND:19960920T220000Z
- STATUS:CONFIRMED
- CATEGORIES:CONFERENCE
- SUMMARY:Networld+Interop Conference
- DESCRIPTION:Networld+Interop Conference
- and Exhibit\nAtlanta World Congress Center\n
- Atlanta\, Georgia
- END:VEVENT
- END:VCALENDAR
-
- The following example specifies a group-scheduled meeting that begins
- at 8:30 AM EST on March 12, 1998 and ends at 9:30 AM EST on March 12,
- 1998. The "Organizer" has scheduled the meeting with one or more
- calendar users in a group. A time zone specification for Eastern
- United States has been specified.
-
- BEGIN:VCALENDAR
- PRODID:-//RDU Software//NONSGML HandCal//EN
- VERSION:2.0
- BEGIN:VTIMEZONE
- TZID:America/New_York
- BEGIN:STANDARD
- DTSTART:19981025T020000
- TZOFFSETFROM:-0400
- TZOFFSETTO:-0500
- TZNAME:EST
- END:STANDARD
- BEGIN:DAYLIGHT
- DTSTART:19990404T020000
- TZOFFSETFROM:-0500
- TZOFFSETTO:-0400
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- TZNAME:EDT
- END:DAYLIGHT
- END:VTIMEZONE
- BEGIN:VEVENT
- DTSTAMP:19980309T231000Z
- UID:guid-1.example.com
- ORGANIZER:mailto:mrbig@example.com
- ATTENDEE;RSVP=TRUE;ROLE=REQ-PARTICIPANT;CUTYPE=GROUP:
- mailto:employee-A@example.com
- DESCRIPTION:Project XYZ Review Meeting
- CATEGORIES:MEETING
- CLASS:PUBLIC
- CREATED:19980309T130000Z
- SUMMARY:XYZ Project Review
- DTSTART;TZID=America/New_York:19980312T083000
- DTEND;TZID=America/New_York:19980312T093000
- LOCATION:1CP Conference Room 4350
- END:VEVENT
- END:VCALENDAR
-
- The following is an example of an iCalendar object passed in a MIME
- message with a single body part consisting of a "text/calendar"
- Content Type.
-
- TO:jsmith@example.com
- FROM:jdoe@example.com
- MIME-VERSION:1.0
- MESSAGE-ID:<id3@example.com>
- CONTENT-TYPE:text/calendar; method="xyz"; component="VEVENT"
-
- BEGIN:VCALENDAR
- METHOD:xyz
- VERSION:2.0
- PRODID:-//ABC Corporation//NONSGML My Product//EN
- BEGIN:VEVENT
- DTSTAMP:19970324T120000Z
- SEQUENCE:0
- UID:uid3@example.com
- ORGANIZER:mailto:jdoe@example.com
- ATTENDEE;RSVP=TRUE:mailto:jsmith@example.com
- DTSTART:19970324T123000Z
- DTEND:19970324T210000Z
- CATEGORIES:MEETING,PROJECT
- CLASS:PUBLIC
- SUMMARY:Calendaring Interoperability Planning Meeting
- DESCRIPTION:Discuss how we can test c&s interoperability\n
- using iCalendar and other IETF standards.
- LOCATION:LDB Lobby
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- ATTACH;FMTTYPE=application/postscript:ftp://example.com/pub/
- conf/bkgrnd.ps
- END:VEVENT
- END:VCALENDAR
-
- The following is an example of a to-do due on April 15, 1998. An
- audio alarm has been specified to remind the calendar user at noon,
- the day before the to-do is expected to be completed and repeat
- hourly, four additional times. The to-do definition has been
- modified twice since it was initially created.
-
- BEGIN:VCALENDAR
- VERSION:2.0
- PRODID:-//ABC Corporation//NONSGML My Product//EN
- BEGIN:VTODO
- DTSTAMP:19980130T134500Z
- SEQUENCE:2
- UID:uid4@example.com
- ORGANIZER:mailto:unclesam@example.com
- ATTENDEE;PARTSTAT=ACCEPTED:mailto:jqpublic@example.com
- DUE:19980415T000000
- STATUS:NEEDS-ACTION
- SUMMARY:Submit Income Taxes
- BEGIN:VALARM
- ACTION:AUDIO
- TRIGGER:19980403T120000Z
- ATTACH;FMTTYPE=audio/basic:http://example.com/pub/audio-
- files/ssbanner.aud
- REPEAT:4
- DURATION:PT1H
- END:VALARM
- END:VTODO
- END:VCALENDAR
-
- The following is an example of a journal entry:
-
- BEGIN:VCALENDAR
- VERSION:2.0
- PRODID:-//ABC Corporation//NONSGML My Product//EN
- BEGIN:VJOURNAL
- DTSTAMP:19970324T120000Z
- UID:uid5@example.com
- ORGANIZER:mailto:jsmith@example.com
- STATUS:DRAFT
- CLASS:PUBLIC
- CATEGORIES:Project Report,XYZ,Weekly Meeting
- DESCRIPTION:Project xyz Review Meeting Minutes\n
- Agenda\n1. Review of project version 1.0 requirements.\n2.
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- Definition
- of project processes.\n3. Review of project schedule.\n
- Participants: John Smith\, Jane Doe\, Jim Dandy\n-It was
- decided that the requirements need to be signed off by
- product marketing.\n-Project processes were accepted.\n
- -Project schedule needs to account for scheduled holidays
- and employee vacation time. Check with HR for specific
- dates.\n-New schedule will be distributed by Friday.\n-
- Next weeks meeting is cancelled. No meeting until 3/23.
- END:VJOURNAL
- END:VCALENDAR
-
- The following is an example of published busy time information. The
- iCalendar object might be placed in the network resource
- http://www.example.com/calendar/busytime/jsmith.ifb.
-
- BEGIN:VCALENDAR
- VERSION:2.0
- PRODID:-//RDU Software//NONSGML HandCal//EN
- BEGIN:VFREEBUSY
- ORGANIZER:mailto:jsmith@example.com
- DTSTART:19980313T141711Z
- DTEND:19980410T141711Z
- FREEBUSY:19980314T233000Z/19980315T003000Z
- FREEBUSY:19980316T153000Z/19980316T163000Z
- FREEBUSY:19980318T030000Z/19980318T040000Z
- URL:http://www.example.com/calendar/busytime/jsmith.ifb
- END:VFREEBUSY
- END:VCALENDAR
-
-5. Recommended Practices
-
- These recommended practices should be followed in order to assure
- consistent handling of the following cases for an iCalendar object.
-
- 1. Content lines longer than 75 octets SHOULD be folded.
-
- 2. When the combination of the "RRULE" and "RDATE" properties in a
- recurring component produces multiple instances having the same
- start DATE-TIME value, they should be collapsed to, and
- considered as, a single instance. If the "RDATE" property is
- specified as a PERIOD value the duration of the recurrence
- instance will be the one specified by the "RDATE" property, and
- not the duration of the recurrence instance defined by the
- "DTSTART" property.
-
- 3. When a calendar user receives multiple requests for the same
- calendar component (e.g., REQUEST for a "VEVENT" calendar
-
-
-
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-
-RFC 5545 iCalendar September 2009
-
-
- component) as a result of being on multiple mailing lists
- specified by "ATTENDEE" properties in the request, they SHOULD
- respond to only one of the requests. The calendar user SHOULD
- also specify (using the "MEMBER" parameter of the "ATTENDEE"
- property) of which mailing list they are a member.
-
- 4. An implementation can truncate a "SUMMARY" property value to 255
- octets, but it MUST NOT truncate the value in the middle of a
- UTF-8 multi-octet sequence.
-
- 5. If seconds of the minute are not supported by an implementation,
- then a value of "00" SHOULD be specified for the seconds
- component in a time value.
-
- 6. "TZURL" values SHOULD NOT be specified as a file URI type. This
- URI form can be useful within an organization, but is problematic
- in the Internet.
-
- 7. Some possible English values for "CATEGORIES" property include:
- "ANNIVERSARY", "APPOINTMENT", "BUSINESS", "EDUCATION", "HOLIDAY",
- "MEETING", "MISCELLANEOUS", "NON-WORKING HOURS", "NOT IN OFFICE",
- "PERSONAL", "PHONE CALL", "SICK DAY", "SPECIAL OCCASION",
- "TRAVEL", "VACATION". Categories can be specified in any
- registered language.
-
- 8. Some possible English values for the "RESOURCES" property
- include: "CATERING", "CHAIRS", "COMPUTER PROJECTOR", "EASEL",
- "OVERHEAD PROJECTOR", "SPEAKER PHONE", "TABLE", "TV", "VCR",
- "VIDEO PHONE", "VEHICLE". Resources can be specified in any
- registered language.
-
-6. Internationalization Considerations
-
- Applications MUST generate iCalendar streams in the UTF-8 charset and
- MUST accept an iCalendar stream in the UTF-8 or US-ASCII charset.
-
-7. Security Considerations
-
- Because calendaring and scheduling information is very privacy-
- sensitive, the protocol used for the transmission of calendaring and
- scheduling information should have capabilities to protect the
- information from possible threats, such as eavesdropping, replay,
- message insertion, deletion, modification, and man-in-the-middle
- attacks.
-
- As this document only defines the data format and media type of text/
- calendar that is independent of any calendar service or protocol, it
- is up to the actual protocol specifications such as iTIP [2446bis],
-
-
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-
- iMIP [2447bis], and "Calendaring Extensions to WebDAV (CalDAV)"
- [RFC4791] to describe the threats that the above attacks present, as
- well as ways in which to mitigate them.
-
-8. IANA Considerations
-
-8.1. iCalendar Media Type Registration
-
- The Calendaring and Scheduling Core Object Specification is intended
- for use as a MIME content type.
-
- To: ietf-types@iana.org
-
- Subject: Registration of media type text/calendar
-
- Type name: text
-
- Subtype name: calendar
-
- Required parameters: none
-
- Optional parameters: charset, method, component, and optinfo
-
- The "charset" parameter is defined in [RFC2046] for subtypes of
- the "text" media type. It is used to indicate the charset used in
- the body part. The charset supported by this revision of
- iCalendar is UTF-8. The use of any other charset is deprecated by
- this revision of iCalendar; however, note that this revision
- requires that compliant applications MUST accept iCalendar streams
- using either the UTF-8 or US-ASCII charset.
-
- The "method" parameter is used to convey the iCalendar object
- method or transaction semantics for the calendaring and scheduling
- information. It also is an identifier for the restricted set of
- properties and values of which the iCalendar object consists. The
- parameter is to be used as a guide for applications interpreting
- the information contained within the body part. It SHOULD NOT be
- used to exclude or require particular pieces of information unless
- the identified method definition specifically calls for this
- behavior. Unless specifically forbidden by a particular method
- definition, a text/calendar content type can contain any set of
- properties permitted by the Calendaring and Scheduling Core Object
- Specification. The "method" parameter MUST be specified and MUST
- be set to the same value as the "METHOD" component property of the
- iCalendar objects of the iCalendar stream if and only if the
- iCalendar objects in the iCalendar stream all have a "METHOD"
- component property set to the same value.
-
-
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-
- The value for the "method" parameter is defined as follows:
-
- method = 1*(ALPHA / DIGIT / "-")
- ; IANA-registered iCalendar object method
-
- The "component" parameter conveys the type of iCalendar calendar
- component within the body part. If the iCalendar object contains
- more than one calendar component type, then multiple component
- parameters MUST be specified.
-
- The value for the "component" parameter is defined as follows:
-
- component = "VEVENT"
- / "VTODO"
- / "VJOURNAL"
- / "VFREEBUSY"
- / "VTIMEZONE"
- / iana-token
- / x-name
-
- The "optinfo" parameter conveys optional information about the
- iCalendar object within the body part. This parameter can only
- specify semantics already specified by the iCalendar object and
- that can be otherwise determined by parsing the body part. In
- addition, the optional information specified by this parameter
- MUST be consistent with that information specified by the
- iCalendar object. For example, it can be used to convey the
- "Attendee" response status to a meeting request. The parameter
- value consists of a string value.
-
- The parameter can be specified multiple times.
-
- The value for the "optinfo" parameter is defined as follows:
-
- optinfo = infovalue / qinfovalue
-
- infovalue = iana-token / x-name
-
- qinfovalue = DQUOTE (infovalue) DQUOTE
-
- Encoding considerations: This media type can contain 8bit
- characters, so the use of quoted-printable or base64 MIME Content-
- Transfer-Encodings might be necessary when iCalendar objects are
- transferred across protocols restricted to the 7bit repertoire.
- Note that a text valued property in the content entity can also
- have content encoding of special characters using a BACKSLASH
- character escapement technique. This means that content values
- can end up being encoded twice.
-
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-
- Security considerations: See Section 7.
-
- Interoperability considerations: This media type is intended to
- define a common format for conveying calendaring and scheduling
- information between different systems. It is heavily based on the
- earlier [VCAL] industry specification.
-
- Published specification: This specification.
-
- Applications that use this media type: This media type is designed
- for widespread use by Internet calendaring and scheduling
- applications. In addition, applications in the workflow and
- document management area might find this content-type applicable.
- The iTIP [2446bis], iMIP [2447bis], and CalDAV [RFC4791] Internet
- protocols directly use this media type also.
-
- Additional information:
-
- Magic number(s): None.
-
- File extension(s): The file extension of "ics" is to be used to
- designate a file containing (an arbitrary set of) calendaring
- and scheduling information consistent with this MIME content
- type.
-
- The file extension of "ifb" is to be used to designate a file
- containing free or busy time information consistent with this
- MIME content type.
-
- Macintosh file type code(s): The file type code of "iCal" is to
- be used in Apple MacIntosh operating system environments to
- designate a file containing calendaring and scheduling
- information consistent with this MIME media type.
-
- The file type code of "iFBf" is to be used in Apple MacIntosh
- operating system environments to designate a file containing
- free or busy time information consistent with this MIME media
- type.
-
- Person & email address to contact for further information: See the
- "Author's Address" section of this document.
-
- Intended usage: COMMON
-
- Restrictions on usage: There are no restrictions on where this media
- type can be used.
-
- Author: See the "Author's Address" section of this document.
-
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-
- Change controller: IETF
-
-8.2. New iCalendar Elements Registration
-
- This section defines the process to register new or modified
- iCalendar elements, that is, components, properties, parameters,
- value data types, and values, with IANA.
-
-8.2.1. iCalendar Elements Registration Procedure
-
- The IETF will create a mailing list, icalendar@ietf.org, which can be
- used for public discussion of iCalendar elements proposals prior to
- registration. Use of the mailing list is strongly encouraged. The
- IESG will appoint a designated expert who will monitor the
- icalendar@ietf.org mailing list and review registrations.
-
- Registration of new iCalendar elements MUST be reviewed by the
- designated expert and published in an RFC. A Standards Track RFC is
- REQUIRED for the registration of new value data types that modify
- existing properties, as well as for the registration of participation
- status values to be used in "VEVENT" calendar components. A
- Standards Track RFC is also REQUIRED for registration of iCalendar
- elements that modify iCalendar elements previously documented in a
- Standards Track RFC.
-
- The registration procedure begins when a completed registration
- template, defined in the sections below, is sent to
- icalendar@ietf.org and iana@iana.org. The designated expert is
- expected to tell IANA and the submitter of the registration within
- two weeks whether the registration is approved, approved with minor
- changes, or rejected with cause. When a registration is rejected
- with cause, it can be re-submitted if the concerns listed in the
- cause are addressed. Decisions made by the designated expert can be
- appealed to the IESG Applications Area Director, then to the IESG.
- They follow the normal appeals procedure for IESG decisions.
-
-8.2.2. Registration Template for Components
-
- A component is defined by completing the following template.
-
- Component name: The name of the component.
-
- Purpose: The purpose of the component. Give a short but clear
- description.
-
- Format definition: The ABNF for the component definition needs to be
- specified.
-
-
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-
- Description: Any special notes about the component, how it is to be
- used, etc.
-
- Example(s): One or more examples of instances of the component need
- to be specified.
-
-8.2.3. Registration Template for Properties
-
- A property is defined by completing the following template.
-
- Property name: The name of the property.
-
- Purpose: The purpose of the property. Give a short but clear
- description.
-
- Value type: Any of the valid value types for the property value need
- to be specified. The default value type also needs to be
- specified.
-
- Property parameters: Any of the valid property parameters for the
- property MUST be specified.
-
- Conformance: The calendar components in which the property can
- appear MUST be specified.
-
- Description: Any special notes about the property, how it is to be
- used, etc.
-
- Format definition: The ABNF for the property definition needs to be
- specified.
-
- Example(s): One or more examples of instances of the property need
- to be specified.
-
-8.2.4. Registration Template for Parameters
-
- A parameter is defined by completing the following template.
-
- Parameter name: The name of the parameter.
-
- Purpose: The purpose of the parameter. Give a short but clear
- description.
-
- Format definition: The ABNF for the parameter definition needs to be
- specified.
-
- Description: Any special notes about the parameter, how it is to be
- used, etc.
-
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-
- Example(s): One or more examples of instances of the parameter need
- to be specified.
-
-8.2.5. Registration Template for Value Data Types
-
- A value data type is defined by completing the following template.
-
- Value name: The name of the value type.
-
- Purpose: The purpose of the value type. Give a short but clear
- description.
-
- Format definition: The ABNF for the value type definition needs to
- be specified.
-
- Description: Any special notes about the value type, how it is to be
- used, etc.
-
- Example(s): One or more examples of instances of the value type need
- to be specified.
-
-8.2.6. Registration Template for Values
-
- A value is defined by completing the following template.
-
- Value: The value literal.
-
- Purpose: The purpose of the value. Give a short but clear
- description.
-
- Conformance: The calendar properties and/or parameters that can take
- this value need to be specified.
-
- Example(s): One or more examples of instances of the value need to
- be specified.
-
- The following is a fictitious example of a registration of an
- iCalendar value:
-
- Value: TOP-SECRET
-
- Purpose: This value is used to specify the access classification of
- top-secret calendar components.
-
- Conformance: This value can be used with the "CLASS" property.
-
-
-
-
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-
-
- Example(s): The following is an example of this value used with the
- "CLASS" property:
-
- CLASS:TOP-SECRET
-
-8.3. Initial iCalendar Elements Registries
-
- The IANA created and maintains the following registries for iCalendar
- elements with pointers to appropriate reference documents.
-
-8.3.1. Components Registry
-
- The following table has been used to initialize the components
- registry.
-
- +-----------+---------+-------------------------+
- | Component | Status | Reference |
- +-----------+---------+-------------------------+
- | VCALENDAR | Current | RFC 5545, Section 3.4 |
- | | | |
- | VEVENT | Current | RFC 5545, Section 3.6.1 |
- | | | |
- | VTODO | Current | RFC 5545, Section 3.6.2 |
- | | | |
- | VJOURNAL | Current | RFC 5545, Section 3.6.3 |
- | | | |
- | VFREEBUSY | Current | RFC 5545, Section 3.6.4 |
- | | | |
- | VTIMEZONE | Current | RFC 5545, Section 3.6.5 |
- | | | |
- | VALARM | Current | RFC 5545, Section 3.6.6 |
- | | | |
- | STANDARD | Current | RFC 5545, Section 3.6.5 |
- | | | |
- | DAYLIGHT | Current | RFC 5545, Section 3.6.5 |
- +-----------+---------+-------------------------+
-
-
-
-
-
-
-
-
-
-
-
-
-
-
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-
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-
-8.3.2. Properties Registry
-
- The following table is has been used to initialize the properties
- registry.
-
- +------------------+------------+----------------------------+
- | Property | Status | Reference |
- +------------------+------------+----------------------------+
- | CALSCALE | Current | RFC 5545, Section 3.7.1 |
- | METHOD | Current | RFC 5545, Section 3.7.2 |
- | | | |
- | PRODID | Current | RFC 5545, Section 3.7.3 |
- | | | |
- | VERSION | Current | RFC 5545, Section 3.7.4 |
- | | | |
- | ATTACH | Current | RFC 5545, Section 3.8.1.1 |
- | | | |
- | CATEGORIES | Current | RFC 5545, Section 3.8.1.2 |
- | | | |
- | CLASS | Current | RFC 5545, Section 3.8.1.3 |
- | | | |
- | COMMENT | Current | RFC 5545, Section 3.8.1.4 |
- | | | |
- | DESCRIPTION | Current | RFC 5545, Section 3.8.1.5 |
- | | | |
- | GEO | Current | RFC 5545, Section 3.8.1.6 |
- | | | |
- | LOCATION | Current | RFC 5545, Section 3.8.1.7 |
- | | | |
- | PERCENT-COMPLETE | Current | RFC 5545, Section 3.8.1.8 |
- | | | |
- | PRIORITY | Current | RFC 5545, Section 3.8.1.9 |
- | | | |
- | RESOURCES | Current | RFC 5545, Section 3.8.1.10 |
- | | | |
- | STATUS | Current | RFC 5545, Section 3.8.1.11 |
- | | | |
- | SUMMARY | Current | RFC 5545, Section 3.8.1.12 |
- | | | |
- | COMPLETED | Current | RFC 5545, Section 3.8.2.1 |
- | | | |
- | DTEND | Current | RFC 5545, Section 3.8.2.2 |
- | | | |
- | DUE | Current | RFC 5545, Section 3.8.2.3 |
- | | | |
- | DTSTART | Current | RFC 5545, Section 3.8.2.4 |
- | | | |
- | DURATION | Current | RFC 5545, Section 3.8.2.5 |
-
-
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-
- | | | |
- | FREEBUSY | Current | RFC 5545, Section 3.8.2.6 |
- | | | |
- | TRANSP | Current | RFC 5545, Section 3.8.2.7 |
- | | | |
- | TZID | Current | RFC 5545, Section 3.8.3.1 |
- | | | |
- | TZNAME | Current | RFC 5545, Section 3.8.3.2 |
- | | | |
- | TZOFFSETFROM | Current | RFC 5545, Section 3.8.3.3 |
- | | | |
- | TZOFFSETTO | Current | RFC 5545, Section 3.8.3.4 |
- | | | |
- | TZURL | Current | RFC 5545, Section 3.8.3.5 |
- | | | |
- | ATTENDEE | Current | RFC 5545, Section 3.8.4.1 |
- | | | |
- | CONTACT | Current | RFC 5545, Section 3.8.4.2 |
- | | | |
- | ORGANIZER | Current | RFC 5545, Section 3.8.4.3 |
- | | | |
- | RECURRENCE-ID | Current | RFC 5545, Section 3.8.4.4 |
- | | | |
- | RELATED-TO | Current | RFC 5545, Section 3.8.4.5 |
- | | | |
- | URL | Current | RFC 5545, Section 3.8.4.6 |
- | | | |
- | UID | Current | RFC 5545, Section 3.8.4.7 |
- | | | |
- | EXDATE | Current | RFC 5545, Section 3.8.5.1 |
- | | | |
- | EXRULE | Deprecated | [RFC2445], Section 4.8.5.2 |
- | | | |
- | RDATE | Current | RFC 5545, Section 3.8.5.2 |
- | | | |
- | RRULE | Current | RFC 5545, Section 3.8.5.3 |
- | | | |
- | ACTION | Current | RFC 5545, Section 3.8.6.1 |
- | | | |
- | REPEAT | Current | RFC 5545, Section 3.8.6.2 |
- | | | |
- | TRIGGER | Current | RFC 5545, Section 3.8.6.3 |
- | | | |
- | CREATED | Current | RFC 5545, Section 3.8.7.1 |
- | | | |
- | DTSTAMP | Current | RFC 5545, Section 3.8.7.2 |
- | | | |
- | LAST-MODIFIED | Current | RFC 5545, Section 3.8.7.3 |
-
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-
- | | | |
- | SEQUENCE | Current | RFC 5545, Section 3.8.7.4 |
- | | | |
- | REQUEST-STATUS | Current | RFC 5545, Section 3.8.8.3 |
- +------------------+------------+----------------------------+
-
-8.3.3. Parameters Registry
-
- The following table has been used to initialize the parameters
- registry.
-
- +----------------+---------+--------------------------+
- | Parameter | Status | Reference |
- +----------------+---------+--------------------------+
- | ALTREP | Current | RFC 5545, Section 3.2.1 |
- | | | |
- | CN | Current | RFC 5545, Section 3.2.2 |
- | | | |
- | CUTYPE | Current | RFC 5545, Section 3.2.3 |
- | | | |
- | DELEGATED-FROM | Current | RFC 5545, Section 3.2.4 |
- | | | |
- | DELEGATED-TO | Current | RFC 5545, Section 3.2.5 |
- | | | |
- | DIR | Current | RFC 5545, Section 3.2.6 |
- | | | |
- | ENCODING | Current | RFC 5545, Section 3.2.7 |
- | | | |
- | FMTTYPE | Current | RFC 5545, Section 3.2.8 |
- | | | |
- | FBTYPE | Current | RFC 5545, Section 3.2.9 |
- | | | |
- | LANGUAGE | Current | RFC 5545, Section 3.2.10 |
- | | | |
- | MEMBER | Current | RFC 5545, Section 3.2.11 |
- | | | |
- | PARTSTAT | Current | RFC 5545, Section 3.2.12 |
- | | | |
- | RANGE | Current | RFC 5545, Section 3.2.13 |
- | | | |
- | RELATED | Current | RFC 5545, Section 3.2.14 |
- | | | |
- | RELTYPE | Current | RFC 5545, Section 3.2.15 |
- | | | |
- | ROLE | Current | RFC 5545, Section 3.2.16 |
- | | | |
- | RSVP | Current | RFC 5545, Section 3.2.17 |
- | | | |
-
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-
- | SENT-BY | Current | RFC 5545, Section 3.2.18 |
- | | | |
- | TZID | Current | RFC 5545, Section 3.2.19 |
- | | | |
- | VALUE | Current | RFC 5545, Section 3.2.20 |
- +----------------+---------+--------------------------+
-
-8.3.4. Value Data Types Registry
-
- The following table has been used to initialize the value data types
- registry.
-
- +-----------------+---------+--------------------------+
- | Value Data Type | Status | Reference |
- +-----------------+---------+--------------------------+
- | BINARY | Current | RFC 5545, Section 3.3.1 |
- | | | |
- | BOOLEAN | Current | RFC 5545, Section 3.3.2 |
- | | | |
- | CAL-ADDRESS | Current | RFC 5545, Section 3.3.3 |
- | | | |
- | DATE | Current | RFC 5545, Section 3.3.4 |
- | | | |
- | DATE-TIME | Current | RFC 5545, Section 3.3.5 |
- | | | |
- | DURATION | Current | RFC 5545, Section 3.3.6 |
- | | | |
- | FLOAT | Current | RFC 5545, Section 3.3.7 |
- | | | |
- | INTEGER | Current | RFC 5545, Section 3.3.8 |
- | | | |
- | PERIOD | Current | RFC 5545, Section 3.3.9 |
- | | | |
- | RECUR | Current | RFC 5545, Section 3.3.10 |
- | | | |
- | TEXT | Current | RFC 5545, Section 3.3.11 |
- | | | |
- | TIME | Current | RFC 5545, Section 3.3.12 |
- | | | |
- | URI | Current | RFC 5545, Section 3.3.13 |
- | | | |
- | UTC-OFFSET | Current | RFC 5545, Section 3.3.14 |
- +-----------------+---------+--------------------------+
-
-
-
-
-
-
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-
-8.3.5. Calendar User Types Registry
-
- The following table has been used to initialize the calendar user
- types registry.
-
- +--------------------+---------+-------------------------+
- | Calendar User Type | Status | Reference |
- +--------------------+---------+-------------------------+
- | INDIVIDUAL | Current | RFC 5545, Section 3.2.3 |
- | | | |
- | GROUP | Current | RFC 5545, Section 3.2.3 |
- | | | |
- | RESOURCE | Current | RFC 5545, Section 3.2.3 |
- | | | |
- | ROOM | Current | RFC 5545, Section 3.2.3 |
- | | | |
- | UNKNOWN | Current | RFC 5545, Section 3.2.3 |
- +--------------------+---------+-------------------------+
-
-8.3.6. Free/Busy Time Types Registry
-
- The following table has been used to initialize the free/busy time
- types registry.
-
- +---------------------+---------+-------------------------+
- | Free/Busy Time Type | Status | Reference |
- +---------------------+---------+-------------------------+
- | FREE | Current | RFC 5545, Section 3.2.9 |
- | | | |
- | BUSY | Current | RFC 5545, Section 3.2.9 |
- | | | |
- | BUSY-UNAVAILABLE | Current | RFC 5545, Section 3.2.9 |
- | | | |
- | BUSY-TENTATIVE | Current | RFC 5545, Section 3.2.9 |
- +---------------------+---------+-------------------------+
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
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-
-
-8.3.7. Participation Statuses Registry
-
- The following table has been used to initialize the participation
- statuses registry.
-
- +--------------------+---------+--------------------------+
- | Participant Status | Status | Reference |
- +--------------------+---------+--------------------------+
- | NEEDS-ACTION | Current | RFC 5545, Section 3.2.12 |
- | | | |
- | ACCEPTED | Current | RFC 5545, Section 3.2.12 |
- | | | |
- | DECLINED | Current | RFC 5545, Section 3.2.12 |
- | | | |
- | TENTATIVE | Current | RFC 5545, Section 3.2.12 |
- | | | |
- | DELEGATED | Current | RFC 5545, Section 3.2.12 |
- | | | |
- | COMPLETED | Current | RFC 5545, Section 3.2.12 |
- | | | |
- | IN-PROCESS | Current | RFC 5545, Section 3.2.12 |
- +--------------------+---------+--------------------------+
-
-8.3.8. Relationship Types Registry
-
- The following table has been used to initialize the relationship
- types registry.
-
- +-------------------+---------+--------------------------+
- | Relationship Type | Status | Reference |
- +-------------------+---------+--------------------------+
- | CHILD | Current | RFC 5545, Section 3.2.15 |
- | | | |
- | PARENT | Current | RFC 5545, Section 3.2.15 |
- | | | |
- | SIBLING | Current | RFC 5545, Section 3.2.15 |
- +-------------------+---------+--------------------------+
-
-
-
-
-
-
-
-
-
-
-
-
-
-
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-
-
-8.3.9. Participation Roles Registry
-
- The following table has been used to initialize the participation
- roles registry.
-
- +-----------------+---------+--------------------------+
- | Role Type | Status | Reference |
- +-----------------+---------+--------------------------+
- | CHAIR | Current | RFC 5545, Section 3.2.16 |
- | | | |
- | REQ-PARTICIPANT | Current | RFC 5545, Section 3.2.16 |
- | | | |
- | OPT-PARTICIPANT | Current | RFC 5545, Section 3.2.16 |
- | | | |
- | NON-PARTICIPANT | Current | RFC 5545, Section 3.2.16 |
- +-----------------+---------+--------------------------+
-
-8.3.10. Actions Registry
-
- The following table has been used to initialize the actions registry.
-
- +-----------+------------+----------------------------+
- | Action | Status | Reference |
- +-----------+------------+----------------------------+
- | AUDIO | Current | RFC 5545, Section 3.8.6.1 |
- | | | |
- | DISPLAY | Current | RFC 5545, Section 3.8.6.1 |
- | | | |
- | EMAIL | Current | RFC 5545, Section 3.8.6.1 |
- | | | |
- | PROCEDURE | Deprecated | [RFC2445], Section 4.8.6.1 |
- +-----------+------------+----------------------------+
-
-8.3.11. Classifications Registry
-
- The following table has been used to initialize the classifications
- registry.
-
- +----------------+---------+---------------------------+
- | Classification | Status | Reference |
- +----------------+---------+---------------------------+
- | PUBLIC | Current | RFC 5545, Section 3.8.1.3 |
- | | | |
- | PRIVATE | Current | RFC 5545, Section 3.8.1.3 |
- | | | |
- | CONFIDENTIAL | Current | RFC 5545, Section 3.8.1.3 |
- +----------------+---------+---------------------------+
-
-
-
-
-Desruisseaux Standards Track [Page 162]
-
-RFC 5545 iCalendar September 2009
-
-
-8.3.12. Methods Registry
-
- No values are defined in this document for the "METHOD" property.
-
-9. Acknowledgments
-
- The editor of this document wishes to thank Frank Dawson and Derik
- Stenerson, the original authors of RFC 2445, as well as the following
- individuals who have participated in the drafting, review, and
- discussion of this memo:
-
- Joe Abley, Hervey Allen, Steve Allen, Jay Batson, Oliver Block,
- Stephane Bortzmeyer, Chris Bryant, Tantek Celik, Mark Crispin, Cyrus
- Daboo, Mike Douglass, Andrew N. Dowden, Lisa Dusseault, Lars Eggert,
- Gren Eliot, Pasi Eronen, Ben Fortuna, Ned Freed, Neal Gafter, Ted
- Hardie, Tim Hare, Jeffrey Harris, Helge Hess, Paul B. Hill, Thomas
- Hnetila, Russ Housley, Leif Johansson, Ciny Joy, Bruce Kahn, Reinhold
- Kainhofer, Martin Kiff, Patrice Lapierre, Michiel van Leeuwen,
- Jonathan Lennox, Jeff McCullough, Bill McQuillan, Alexey Melnikov,
- John W. Noerenberg II, Chuck Norris, Mark Paterson, Simon Pilette,
- Arnaud Quillaud, Robert Ransdell, Julian F. Reschke, Caleb
- Richardson, Sam Roberts, Dan Romascanu, Mike Samuel, George Sexton,
- Nigel Swinson, Clint Talbert, Simon Vaillancourt, Magnus Westerlund,
- and Sandy Wills.
-
- A special thanks to the working group chairs Aki Niemi and Eliot Lear
- for their support and guidance.
-
- The editor would also like to thank the Calendaring and Scheduling
- Consortium for advice with this specification, and for organizing
- interoperability testing events to help refine it.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-Desruisseaux Standards Track [Page 163]
-
-RFC 5545 iCalendar September 2009
-
-
-10. References
-
-10.1. Normative References
-
- [ISO.8601.2004] International Organization for
- Standardization, "Data elements and
- interchange formats -- Information interchange
- -- Representation of dates and times", 2004.
-
- [ISO.9070.1991] International Organization for
- Standardization, "Information Technology_SGML
- Support Facilities -- Registration Procedures
- for Public Text Owner Identifiers, Second
- Edition", April 1991.
-
- [RFC2045] Freed, N. and N. Borenstein, "Multipurpose
- Internet Mail Extensions (MIME) Part One:
- Format of Internet Message Bodies", RFC 2045,
- November 1996.
-
- [RFC2046] Freed, N. and N. Borenstein, "Multipurpose
- Internet Mail Extensions (MIME) Part Two:
- Media Types", RFC 2046, November 1996.
-
- [RFC2119] Bradner, S., "Key words for use in RFCs to
- Indicate Requirement Levels", BCP 14,
- RFC 2119, March 1997.
-
- [RFC2368] Hoffman, P., Masinter, L., and J. Zawinski,
- "The mailto URL scheme", RFC 2368, July 1998.
-
- [RFC3629] Yergeau, F., "UTF-8, a transformation format
- of ISO 10646", STD 63, RFC 3629,
- November 2003.
-
- [RFC3986] Berners-Lee, T., Fielding, R., and L.
- Masinter, "Uniform Resource Identifier (URI):
- Generic Syntax", STD 66, RFC 3986,
- January 2005.
-
- [RFC4288] Freed, N. and J. Klensin, "Media Type
- Specifications and Registration Procedures",
- BCP 13, RFC 4288, December 2005.
-
- [RFC4648] Josefsson, S., "The Base16, Base32, and Base64
- Data Encodings", RFC 4648, October 2006.
-
-
-
-
-
-Desruisseaux Standards Track [Page 164]
-
-RFC 5545 iCalendar September 2009
-
-
- [RFC5234] Crocker, D. and P. Overell, "Augmented BNF for
- Syntax Specifications: ABNF", STD 68,
- RFC 5234, January 2008.
-
- [RFC5646] Phillips, A., Ed., and M. Davis, Ed., "Tags
- for Identifying Languages", BCP 47, RFC 5646,
- September 2009.
-
- [US-ASCII] American National Standards Institute, "Coded
- Character Set - 7-bit American Standard Code
- for Information Interchange", ANSI X3.4, 1986.
-
-10.2. Informative References
-
- [2446bis] Daboo, C., "iCalendar Transport-Independent
- Interoperability Protocol (iTIP)", Work
- in Progress, April 2009.
-
- [2447bis] Melnikov, A., "iCalendar Message-Based
- Interoperability Protocol (iMIP)", Work
- in Progress, June 2008.
-
- [ANSI INCITS 61-1986] International Committee for Information
- Technology, "Representation of Geographic
- Point Locations for Information Interchange
- (formerly ANSI X3.61-1986 (R1997))", ANSI
- INCITS 61-1986 (R2007), 2007.
-
- [RFC1738] Berners-Lee, T., Masinter, L., and M.
- McCahill, "Uniform Resource Locators (URL)",
- RFC 1738, December 1994.
-
- [RFC2392] Levinson, E., "Content-ID and Message-ID
- Uniform Resource Locators", RFC 2392,
- August 1998.
-
- [RFC2397] Masinter, L., "The "data" URL scheme",
- RFC 2397, August 1998.
-
- [RFC2425] Howes, T., Smith, M., and F. Dawson, "A MIME
- Content-Type for Directory Information",
- RFC 2425, September 1998.
-
- [RFC2426] Dawson, F. and T. Howes, "vCard MIME Directory
- Profile", RFC 2426, September 1998.
-
-
-
-
-
-
-Desruisseaux Standards Track [Page 165]
-
-RFC 5545 iCalendar September 2009
-
-
- [RFC2445] Dawson, F. and Stenerson, D., "Internet
- Calendaring and Scheduling Core Object
- Specification (iCalendar)", RFC 2445,
- November 1998.
-
- [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk,
- H., Masinter, L., Leach, P., and T. Berners-
- Lee, "Hypertext Transfer Protocol --
- HTTP/1.1", RFC 2616, June 1999.
-
- [RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818,
- May 2000.
-
- [RFC4516] Smith, M. and T. Howes, "Lightweight Directory
- Access Protocol (LDAP): Uniform Resource
- Locator", RFC 4516, June 2006.
-
- [RFC4791] Daboo, C., Desruisseaux, B., and L. Dusseault,
- "Calendaring Extensions to WebDAV (CalDAV)",
- RFC 4791, March 2007.
-
- [TZDB] Eggert, P. and A.D. Olson, "Sources for Time
- Zone and Daylight Saving Time Data",
- July 2009,
- <http://www.twinsun.com/tz/tz-link.htm>.
-
- [VCAL] Internet Mail Consortium, "vCalendar: The
- Electronic Calendaring and Scheduling Exchange
- Format", September 1996,
- <http://www.imc.org/pdi/vcal-10.txt>.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-Desruisseaux Standards Track [Page 166]
-
-RFC 5545 iCalendar September 2009
-
-
-Appendix A. Differences from RFC 2445
-
- This appendix contains a list of changes that have been made in the
- Internet Calendaring and Scheduling Core Object Specification from
- RFC 2445.
-
-A.1. New Restrictions
-
- 1. The "DTSTART" property SHOULD be synchronized with the recurrence
- rule, if specified.
-
- 2. The "RRULE" property SHOULD NOT occur more than once in a
- component.
-
- 3. The BYHOUR, BYMINUTE, and BYSECOND rule parts MUST NOT be
- specified in the "RRULE" property when the "DTSTART" property is
- specified as a DATE value.
-
- 4. The value type of the "DTEND" or "DUE" properties MUST match the
- value type of "DTSTART" property.
-
- 5. The "DURATION" property can no longer appear in "VFREEBUSY"
- components.
-
-A.2. Restrictions Removed
-
- 1. The "DTSTART" and "DTEND" properties are no longer required to be
- specified as date with local time and time zone reference when
- used with a recurrence rule.
-
-A.3. Deprecated Features
-
- 1. The "EXRULE" property can no longer be specified in a component.
-
- 2. The "THISANDPRIOR" value can no longer be used with the "RANGE"
- parameter.
-
- 3. The "PROCEDURE" value can no longer be used with the "ACTION"
- property.
-
- 4. The value type RECUR no longer allows multiple values to be
- specified by a COMMA-separated list of values.
-
- 5. x-name rule parts can no longer be specified in properties of
- RECUR value type (e.g., "RRULE"). x-param can be used on RECUR
- value type properties instead.
-
-
-
-
-
-Desruisseaux Standards Track [Page 167]
-
-RFC 5545 iCalendar September 2009
-
-
-Author's Address
-
- Bernard Desruisseaux (editor)
- Oracle Corporation
- 600 blvd. de Maisonneuve West
- Suite 1900
- Montreal, QC H3A 3J2
- CANADA
-
- EMail: bernard.desruisseaux@oracle.com
- URI: http://www.oracle.com/
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-Desruisseaux Standards Track [Page 168]
-
DIR diff --git a/ics2txt b/ics2txt
@@ -1,89 +1,90 @@
#!/usr/bin/awk -f
-# handle ical agenda and display them in plain text
+
+# display iCal entries in plain text
function leap(yrs)
{
- return (yrs % 4 == 0) && (yrs % 100 != 0) || (yrs % 400 == 0);
+ return (yrs % 4 == 0) && (yrs % 100 != 0) || (yrs % 400 == 0)
}
function days_per_month(mth, yrs)
{
if (mth == 2)
- return 28 + leap(yrs);
+ return 28 + leap(yrs)
else
- return 30 + (mth - (mth > 7)) % 2;
+ return 30 + (mth - (mth > 7)) % 2
}
function to_sec(yrs, mth, day, hrs, min, sec)
{
while (--mth >= 1)
- day += days_per_month(mth, yrs);
+ day += days_per_month(mth, yrs)
while (--yrs >= 1970)
- day += 365 + leap(yrs);
- return (((((day - 1) * 24) + hrs) * 60) + min) * 60 + sec;
+ day += 365 + leap(yrs)
+ return (((((day - 1) * 24) + hrs) * 60) + min) * 60 + sec
}
function to_date(fmt, sec)
{
for (yrs = 1970; sec >= (s = 3600 * 24 * (365 + leap(yrs))); yrs++)
- sec -= s;
+ sec -= s
for (mth = 1; sec >= (s = 3600 * 24 * days_per_month(mth, yrs)); mth++)
- sec -= s;
+ sec -= s
for (day = 1; sec >= (s = 3600 * 24); day++)
- sec -= s;
+ sec -= s
for (hrs = 0; sec >= 3600; hrs++)
- sec -= 3600;
+ sec -= 3600
for (min = 0; sec >= 60; min++)
- sec -= 60;
- return sprintf(fmt, yrs, mth, day, hrs, min, sec);
+ sec -= 60
+ return sprintf(fmt, yrs, mth, day, hrs, min, sec)
}
function date_ical(str, offset) {
- yrs = substr(str, 1, 4);
- mth = substr(str, 5, 2);
- day = substr(str, 7, 2);
- hrs = substr(str, 10, 2);
- min = substr(str, 12, 2);
+ yrs = substr(str, 1, 4)
+ mth = substr(str, 5, 2)
+ day = substr(str, 7, 2)
+ hrs = substr(str, 10, 2)
+ min = substr(str, 12, 2)
if (substr(str, 16, 1) == "Z")
- return to_sec(yrs, mth, day, hrs, min, 0);
+ return to_sec(yrs, mth, day, hrs, min, 0)
else
- return to_sec(yrs, mth, day, hrs, min, 0) - offset;
+ return to_sec(yrs, mth, day, hrs, min, 0) - offset
}
function date_iso8601(date, offset)
{
- yrs = substr(date, 1, 4);
- mth = substr(date, 6, 2);
- day = substr(date, 9, 2);
- hrs = substr(date, 12, 2);
- min = substr(date, 15, 2);
- return to_sec(yrs, mth, day, hrs, min, 0) - offset;
+ yrs = substr(date, 1, 4)
+ mth = substr(date, 6, 2)
+ day = substr(date, 9, 2)
+ hrs = substr(date, 12, 2)
+ min = substr(date, 15, 2)
+ return to_sec(yrs, mth, day, hrs, min, 0) - offset
}
function swap(array, a, b)
{
- tmp = array[a];
- array[a] = array[b];
- array[b] = tmp;
+ tmp = array[a]
+ array[a] = array[b]
+ array[b] = tmp
}
function sort(array, beg, end)
{
if (beg >= end) # end recursion
- return;
+ return
a = beg + 1; # #1 is the pivot
- b = end;
+ b = end
while (a < b) {
while (a < b && array[a] <= array[beg]) # beg: skip lesser
- a++;
+ a++
while (a < b && array[b] > array[beg]) # end: skip greater
- b--;
+ b--
swap(array, a, b); # found 2 misplaced
}
if (array[beg] > array[a]) # put the pivot back
- swap(array, beg, a);
+ swap(array, beg, a)
sort(array, beg, a - 1); # sort lower half
sort(array, a, end); # sort higher half
@@ -91,99 +92,77 @@ function sort(array, beg, end)
function parse_ical(list, offset)
{
- FS = "[:;]";
+ FS = "[:;]"
while (getline) {
- gsub("\r", " "); gsub("\\\\[ntr]", " "); gsub("\\\\", "");
- gsub("^ *", ""); gsub(" *$", "");
- gsub(" *<[a-zA-Z0-9/]*>* *", "");
+ gsub("\r", " "); gsub("\\\\[ntr]", " "); gsub("\\\\", "")
+ gsub("^ *", ""); gsub(" *$", "")
+ gsub(" *<[a-zA-Z0-9/]*>* *", "")
if (match($0, "^ ")) {
- event[type] = event[type] substr($0, 2, length($0) - 1);
+ event[type] = event[type] substr($0, 2, length($0) - 1)
} else {
- type = $1;
- i = index($0, ":");
- event[type] = substr($0, i + 1, length($0) - i);
+ type = $1
+ i = index($0, ":")
+ event[type] = substr($0, i + 1, length($0) - i)
}
if ($0 ~ /END:VEVENT/)
- list[++nb] = sprintf("%d\t%d\t%s\t%s\t%s\t%s",
+ list[++n] = sprintf("%d\t%d\t%s\t%s\t%s\t%s",
date_ical(event["DTSTART"], offset),
date_ical(event["DTEND"], offset),
- event["CATEGORIES"],
event["SUMMARY"],
event["LOCATION"],
- event["DESCRIPTION"]);
- }
- sort(list, 1, nb);
- return nb;
-}
-
-function txt_one(beg, end, cat, sum, loc, des, offset) {
- b = to_date("%04d/%02d/%02d %02d:%02d", beg + offset);
- e = to_date("%04d/%02d/%02d %02d:%02d", end + offset);
- b_mth = substr(b, 1, 7);
- b_day = substr(b, 9, 2);
- e_day = substr(e, 9, 2);
- b_hrs = substr(b, 12);
- e_hrs = substr(e, 12);
-
- printf("%s\n%2s %2s %s\n%2s %2s %s%s\n",
- (b_mth != l_mth) ? ("\n[" b_mth "]\n") : (""),
- (b_day != l_day) ? (b_day) : (""), b_hrs, sum,
- (b_day != e_day) ? (e_day) : (""), e_hrs,
- (cat) ? ("[" cat "] ") : (""), loc);
-
- while ((line = substr(des, 1, 66)) != "") {
- if (length(line) == 66)
- sub(" +[^ ]*$", "", line);
- des = substr(des, length(line) + 2);
- sub("^ *", "", line);
- sub("^ *", "", des);
- printf(" %s\n", line);
+ event["DESCRIPTION"])
}
- l_mth = b_mth;
- l_day = b_day;
+ sort(list, 1, n)
+ return n
}
-function txt(offset)
+function print_fold(prefix, s, n)
{
- nb = parse_ical(list, offset);
- for (i = 1; i <= nb; i++) {
- split(list[i], arr, "\t");
- txt_one(arr[1], arr[2], arr[3], arr[4], arr[5], arr[6], offset);
+ while (s != "") {
+ line = substr(s, 1, n)
+ if (length(s) > n) sub(" +[^ \t\r\n]*$", "", line)
+ print prefix line
+ s = substr(s, length(line) + 2)
}
}
-function tsv(offset)
+function print_entry(beg, end, summary, location, description, offset)
{
- nb = parse_ical(list, offset);
- for (i = 1; i <= nb; i++)
- print(list[i]);
-}
+ b = to_date("%04d-%02d-%02d %02d:%02d", beg + offset)
+ e = to_date("%04d-%02d-%02d %02d:%02d", end + offset)
+ date = substr(b, 1, 10)
+ hour_beg = substr(b, 12)
+ hour_end = substr(e, 12)
+
+ if (date != last_date) print "\n" date
+ print "\n" hour_beg "\t" summary
+ done = 0
+ if (category) printf("%s\t%s\n", !done++ ? hour_end : "", category)
+ if (location) printf("%s\t%s\n", !done++ ? hour_end : "", location)
+ if (description) {
+ printf("%s", !done++ ? hour_end : "")
+ print_fold("\t", description, 70)
+ }
-function usage()
-{
- print("usage: ics2txt txt file.ics...");
- print(" ics2txt tsv file.ics...");
+ last_date = date
}
BEGIN {
- "date +%z" | getline offset_str;
- close("date +%z");
+ "date +%z" | getline offset_str
+ close("date +%z")
- offset = substr(offset_str, 2, 2) * 3600;
- offset += substr(offset_str, 4, 2) * 60;
+ offset = substr(offset_str, 2, 2) * 3600
+ offset += substr(offset_str, 4, 2) * 60
if (substr(offset_str, 1, 1) == "-")
- offset *= -1;
-
- if (ARGV[1] == "txt") {
- ARGV[1] = ARGV[--ARGC];
- txt(offset);
- } else if (ARGV[1] == "tsv") {
- ARGV[1] = ARGV[--ARGC];
- tsv(offset);
- } else {
- usage();
+ offset *= -1
+
+ n = parse_ical(list, offset)
+ for (i = 1; i <= n; i++) {
+ split(list[i], arr, "\t")
+ print_entry(arr[1], arr[2], arr[3], arr[4], arr[5], arr[6], offset)
}
+ print ""
}
DIR diff --git a/ics2txt.1 b/ics2txt.1
@@ -6,13 +6,12 @@
.Sh NAME
.
.Nm ics2txt
-.Nd convert ics file to plain text or TSV
+.Nd convert ics file to a simple plain text format
.
.
.Sh SYNOPSIS
.
-.Nm Ic txt Oo +- Oc Ns Ar offset Op Ar ics file...
-.Nm Ic tsv Oo +- Oc Ns Ar offset Op Ar ics file...
+.Nm Ar ics-file...
.
.
.Sh DESCRIPTION
@@ -23,42 +22,6 @@ displays iCalendar
.Ar file
or stdin if not specified in the format described by the command:
.
-.Bl -tag -width indent
-.
-.It Ic txt
-Display the ics2txt(s)
-.Ar file
-as plain text sorted by date.
-.
-.It Ic tsv
-Display the ics2txt(s)
-.Ar file
-as a tab-separated values
-.Pq tsv
-one entry per line, with the following fields in order:
-.
-.Bl -tag -width xDESCRIPTIONx -compact
-.
-.It Dq Li DTSTART
-begin date as an UNIX timestamp
-.
-.It Dq Li DTEND
-end date as an UNIX timestamp
-.
-.It Dq Li CATEGORY
-category
-.
-.It Dq Li SUMMARY
-symmary
-.
-.It Dq Li LOCATION
-location
-.
-.It Dq Li DESCRIPTION
-description
-.
-.El
-.
.
.Sh ENVIRONMENT
.
@@ -74,8 +37,7 @@ Timezone to use for printing the dates.
.
.Xr cal 1 ,
.Xr calendar 1 ,
-.Xr date 1 ,
-.Xr txt2ics 1
+.Xr date 1
.
.Sh STANDARDS
.
DIR diff --git a/txt2ics b/txt2ics
@@ -1,93 +0,0 @@
-#!/usr/bin/awk -f
-
-function prompt(msg)
-{
- if (TTY)
- printf("%s", msg) >"/dev/stderr";
- if (!getline str)
- exit(1);
- return str;
-}
-
-function parse_date(str, tm)
-{
- if (length(str) == 5) {
- "date +%Y/%m/%d" | getline date
- str = date " " str ;
- close("date +%Y/%m/%d");
- }
-
- if (length(str) != 16) {
- print("invalid date length") >"/dev/stderr";
- return -1;
- }
-
- tm["yrs"] = substr(str, 1, 4);
- if (! match(tm["yrs"], "^[0-9]+$")) {
- print("invalid year: " tm["yrs"]) >"/dev/stderr";
- return -1;
- }
-
- tm["mth"] = substr(str, 6, 2);
- if (! match(tm["mth"], "^[0-1][0-9]$")) {
- print("invalid month: " tm["mth"]) >"/dev/stderr";
- return -1;
- }
-
- tm["day"] = substr(str, 9, 2);
- if (! match(tm["day"], "^[0-3][0-9]$")) {
- print("invalid day: " tm["day"]) >"/dev/stderr";
- return -1;
- }
-
- tm["hrs"] = substr(str, 12, 2);
- if (! match(tm["hrs"], "^[0-2][0-9]$")) {
- print("invalid hours: " tm["hrs"]) >"/dev/stderr";
- return -1;
- }
-
- tm["min"] = substr(str, 15, 2);
- if (! match(tm["min"], "^[0-6][0-9]$")) {
- print("invalid minutes: " tm["min"]) >"/dev/stderr";
- return -1;
- }
-
- return 0;
-}
-
-BEGIN {
- TTY = !system("tty >/dev/null");
-
- if (TTY) {
- "date +%Y" | getline yrs
- close("date +%Y");
- system("cal " yrs ">/dev/stderr");
- system("date >/dev/stderr");
- system("date +'%Y/%m/%d %H:%M' >/dev/stderr");
- print("") >"/dev/stderr";
- }
-
- do beg = prompt("Start [YYYY/MM/DD HH:MM] or [HH:MM] for today: ");
- while (parse_date(beg, tm_beg) == -1);
-
- do end = prompt("End [YYYY/MM/DD HH:MM] or [HH:MM] for same day: ");
- while (parse_date(end, tm_end) == -1);
-
- sum = prompt("Summary: ");
- cat = prompt("Category: ");
- loc = prompt("Location: ");
- des = prompt("Description: ");
-
- print("BEGIN:VEVENT");
- print("DTSTART:" \
- tm_beg["yrs"] tm_beg["mth"] tm_beg["day"] "T" \
- tm_beg["hrs"] tm_beg["min"] "00");
- print("DTEND:" \
- tm_end["yrs"] tm_end["mth"] tm_end["day"] "T" \
- tm_end["hrs"] tm_end["min"] "00");
- if (cat) print("CATEGORIES:" cat);
- if (sum) print("SUMMARY:" sum);
- if (des) print("DESCRIPTION:" des);
- if (loc) print("LOCATION:" loc);
- print("END:VEVENT");
-}
DIR diff --git a/txt2ics.1 b/txt2ics.1
@@ -1,51 +0,0 @@
-.Dd $Mdocdate: May 30 2018$
-.Dt TXT2ICS 1
-.Os
-.
-.
-.Sh NAME
-.
-.Nm txt2ics
-.Nd convert plain text to an ics file
-.
-.
-.Sh SYNOPSIS
-.
-.Nm
-.
-.
-.Sh DESCRIPTION
-.
-.Nm
-prompts the user for event information and print them in the iCalendar format.
-If stdin is ont a TTY, it will not print the prompt string and act as a
-converter tool.
-.
-.Pp
-It uses
-.Dq floating events :
-If it is 12:30, it will always be 12:30 of the country he resides in: if he moves
-to another time zone, it will be 12:30 of this new time zone.
-See this as the time zone where the event happen.
-.
-.
-.Sh SEE ALSO
-.
-.Xr cal 1 ,
-.Xr calendar 1 ,
-.Xr date 1 ,
-.Xr ics2txt 1
-.
-.Sh STANDARDS
-.
-.Rs
-.%A Desruisseaux
-.%D September 2009
-.%T Internet Calendaring and Scheduling Core Object Specification (iCalendar)
-.%R RFC 5545
-.Re
-.
-.
-.Sh AUTHORS
-.
-.An Josuah Demangeon Aq Mt mail@josuah.net