IMAPの日付形式

IMAP の日時形式

[1] IMAP で使われる日付形式は、同じ電子メイル関係で使われる形式である RFC2822の日付形式にもやや似ていますが、 微妙に異なり、互換性はありません。

[2] RFC 3501 ABNF 抜粋 :

[4] date-text は必ずしも固定長ではなく、 date-time は必ず固定長になります。 どちらの定義が使われるかは場面によります。

[3] 例 :

[12] 時間帯についてはインターネットメールの時間帯表記も参照。

[7] RFC 1064 - Interactive Mail Access Protocol: Version 2 () <https://tools.ietf.org/html/rfc1064#page-24>

date ::= string in form "dd-mmm-yy hh:mm:ss-zzz"

[8] RFC 1176 - Interactive Mail Access Protocol: Version 2 () <https://tools.ietf.org/html/rfc1176#page-26>

date ::= string in form "dd-mmm-yy hh:mm:ss-zzz"

[9] RFC 1176 - Interactive Mail Access Protocol: Version 2 () <https://tools.ietf.org/html/rfc1176#page-22>

InternalDate " 9-Jun-88 12:55:44 PDT"

[10] RFC 1203 - Interactive Mail Access Protocol: Version 3 () <https://tools.ietf.org/html/rfc1203#page-38>

date ::= string in form "dd-mmm-yy hh:mm:ss-zzz"

[11] () <https://www.mirrorservice.org/sites/ftp.cac.washington.edu/mail/old/IMAP2bis.TXT>

date ::= date_new / date_old

date_new ::= string in form "dd-mmm-yyyy hh:mm:ss -zzzz"

date_old ::= string in form "dd-mmm-yy hh:mm:ss-zzz"

In date_new, the year is now a 4-digit year, and the timezone is a

signed four-digit value of hhmm representing hours and minutes west

of Greenwich (that is, the amount that the given time differs from

Universal Time). Subtracting the timezone from the given time will

give the UT form.

Universal Time is expressed as "+0000".

date_old is hereby declared obsolete, and its usage in new software

is STRONGLY discouraged. However, client implementations MUST

recognize and properly parse it.

RFC-1176 documents the argument to the SEARCH criteria BEFORE, ON, and

SINCE as being either "date" in the text and "string" in the BNF.

These SEARCH criteria arguments are hereby amended to be "day", with

the following syntax:

day ::= day_new / day_old

day_new ::= string in form "dd-mmm-yyyy"

day_old ::= string in form "dd-mmm-yy"

day_old is hereby declared obsolete, and its usage in new software

is STRONGLY discouraged. However, server implementations MUST

recognize and properly parse it.