General-Purpose Mail Package
|Official GNU Software|
decodemail– Decode multipart messages
decodemail utility is a filter program that reads
messages from the input mailbox, decodes “textual” parts of each
multipart message from a base64- or quoted-printable encoding to an
8-bit or 7-bit transfer encoding, and stores the processed messages in
the output mailbox. All messages from the input mailbox are stored in
the output, regardless of whether a change was made.
The message parts deemed to be textual are those whose ‘Content-Type’ header matches a predefined, or user-defined, mime type pattern. In addition, encoded pieces of the ‘From:’, ‘To:’, ‘Subject:’, etc., headers are decoded.
decodemail makes this transformation:
Subject: =?utf-8?Q?The=20Baroque=20Enquirer=20|=20July=202020?= ⇒ Subject: The Baroque Enquirer | July 2020
The built-in list of textual content type patterns is:
text/* application/*shell application/shellscript */x-csrc */x-csource */x-diff */x-patch */x-perl */x-php */x-python */x-sh
These strings are matched as shell globbing patterns (see glob in glob(7) manual page).
More patterns can be added to this list using the
mime.text-type configuration statement.
See mime statement, for a detailed discussion, and the
configuration section below for a simple example.
When processing old mesages you may encounter ‘Content-Type’ headers whose value contains only type, but no subtype. To match such headers, use the pattern without ‘/whatever’ part. E.g. ‘text/*’ matches ‘text/plain’ and ‘text/html’, but does not match ‘text’. On the other hand, ‘t*xt’ does not match ‘text/plain’, but does match ‘text’.
Optionally, the decoded parts can be converted to another character set. By default, the character set is not changed.
This document was generated on August 5, 2021 using makeinfo.Verbatim copying and distribution of this entire article is permitted in any medium, provided this notice is preserved.