[Mew-dist 3120] Re: [Q] Why I can't read message with some Subject ?

[Hidenori Ohta / 太田英憲]

おおた＠ここにメールを書くのは久しぶり、です。

From: Akihiro Motoki <motoki at example.com>
Subject: [Mew-dist 3116] Re: [Q] Why I can't read message with some Subject ?
Date: Thu, 11 Dec 1997 03:13:02 +0900

> 上の二つの場合は、MIME形式のSubject(こんな言い方するのでしょうか？)で、
> たしか書式は、
> =?(文字コード)?(encode形式(B|Q))?(エンコードされた文字列)?=
> にだったと思います。
> # 今手元にrfcもなく、読んだことがないので経験的で知っているだけ
> # なので、間違っている場合は指摘してください。
> # このあたりはどのrfcにあるのでしょう？

RFC2047 ですね。

> 上の二つのSubjectには、encoded words の中に '?' が入っているのが
> うまくデコードできない原因ではないでしょうか。
> encoded words の中に ? が入っていていいのかは、
> rfc がないので確認できません。

RFC には以下のようにありますので、`?' がそのまま入っているのは間違いで
す。

4.2. The "Q" encoding
   The "Q" encoding is similar to the "Quoted-Printable" content-
   transfer-encoding defined in RFC 2045.  It is designed to allow text
   containing mostly ASCII characters to be decipherable on an ASCII
   terminal without decoding.
   (1) Any 8-bit value may be represented by a "=" followed by two
       hexadecimal digits.  For example, if the character set in use
       were ISO-8859-1, the "=" character would thus be encoded as
       "=3D", and a SPACE by "=20".  (Upper case should be used for
       hexadecimal digits "A" through "F".)
   (2) The 8-bit hexadecimal value 20 (e.g., ISO-8859-1 SPACE) may be
       represented as "_" (underscore, ASCII 95.).  (This character may
       not pass through some internetwork mail gateways, but its use
       will greatly enhance readability of "Q" encoded data with mail
       readers that do not support this encoding.)  Note that the "_"
       always represents hexadecimal 20, even if the SPACE character
       occupies a different code position in the character set in use.
   (3) 8-bit values which correspond to printable ASCII characters other
       than "=", "?", and "_" (underscore), MAY be represented as those
       characters.  (But see section 5 for restrictions.)  In
       particular, SPACE and TAB MUST NOT be represented as themselves
       within encoded words.

では
--
ひで