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(python2.1-lib.info)mailcap

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Mailcap file handling.
======================

Mailcap file handling.

Mailcap files are used to configure how MIME-aware applications such as
mail readers and Web browsers react to files with different MIME types.
(The name "mailcap" is derived from the phrase "mail capability".)  For
example, a mailcap file might contain a line like `video/mpeg; xmpeg
%s'.  Then, if the user encounters an email message or Web document
with the MIME type `video/mpeg', `%s' will be replaced by a filename
(usually one belonging to a temporary file) and the `xmpeg' program can
be automatically started to view the file.

The mailcap format is documented in RFC 1524 , "A User Agent
Configuration Mechanism For Multimedia Mail Format Information," but is
not an Internet standard.  However, mailcap files are supported on most
UNIX systems.

`findmatch(caps, MIMEtype                            [, key[, filename[, plist]]])'
     Return a 2-tuple; the first element is a string containing the
     command line to be executed (which can be passed to
     `os.system()'), and the second element is the mailcap entry for a
     given MIME type.  If no matching MIME type can be found, `(None,
     None)' is returned.

     KEY is the name of the field desired, which represents the type of
     activity to be performed; the default value is 'view', since in the
     most common case you simply want to view the body of the MIME-typed
     data.  Other possible values might be 'compose' and 'edit', if you
     wanted to create a new body of the given MIME type or alter the
     existing body data.  See RFC 1524 for a complete list of these
     fields.

     FILENAME is the filename to be substituted for `%s' in the command
     line; the default value is `'/dev/null'' which is almost certainly
     not what you want, so usually you'll override it by specifying a
     filename.

     PLIST can be a list containing named parameters; the default value
     is simply an empty list.  Each entry in the list must be a string
     containing the parameter name, an equals sign (`='), and the
     parameter's value.  Mailcap entries can contain named parameters
     like `%{foo}', which will be replaced by the value of the
     parameter named 'foo'.  For example, if the command line
     `showpartial %{id} %{number} %{total}' was in a mailcap file, and
     PLIST was set to `['id=1', 'number=2', 'total=3']', the resulting
     command line would be `"showpartial 1 2 3"'.

     In a mailcap file, the "test" field can optionally be specified to
     test some external condition (e.g., the machine architecture, or
     the window system in use) to determine whether or not the mailcap
     line applies.  `findmatch()' will automatically check such
     conditions and skip the entry if the check fails.

`getcaps()'
     Returns a dictionary mapping MIME types to a list of mailcap file
     entries. This dictionary must be passed to the `findmatch()'
     function.  An entry is stored as a list of dictionaries, but it
     shouldn't be necessary to know the details of this representation.

     The information is derived from all of the mailcap files found on
     the system. Settings in the user's mailcap file `$HOME/.mailcap'
     will override settings in the system mailcap files `/etc/mailcap',
     `/usr/etc/mailcap', and `/usr/local/etc/mailcap'.

An example usage:
     >>> import mailcap
     >>> d=mailcap.getcaps()
     >>> mailcap.findmatch(d, 'video/mpeg', filename='/tmp/tmp1223')
     ('xmpeg /tmp/tmp1223', {'view': 'xmpeg %s'})