TNEF(1)

NAME
tnef - decode Microsoft's Transport Neutral Encapsulaton Format

SYNOPSIS
tnef [options] [FILE]

tnef {--help | --version}

DESCRIPTION
This manual page documents the tnef filter. tnef decodes e-mail attachments encoded in Microsoft's Transport Neutral Encapsulation Format (hereafter, TNEF), which "wraps" Microsoft e-mail messages composed in Rich Text Format (RTF).

Unfortunately, RTF-rendered attachments are inaccessible to any e-mail client that does not understand TNEF. Fortunately, the tnef filter can be used by any MIME-aware client to decode these attachments.

OPTIONS

-C DIR,  --directory=DIR
    unpack file attachments into DIR.

-f FILE,  --file=FILE
    use FILE as input ('-' denotes stdin). When this option is omitted, tnef reads data from stdin.

--number-backups
    when extracting attachments, if file FOO will be overwritten, create FOO.1 instead.

--overwrite
    when extracting attachments, overwrite existing files.

-t,  --list
    list attached files, do not extract.

--use-paths
    honor file pathnames specifieid in the TNEF attachment. For security reasons, paths to attached files are ignored by default.

-w,  --interactive,  --confirmation
    ask for confirmation for every action.

--debug
    enable debug output.

-v,  --verbose
    produce verbose output.

EXAMPLE
The following example demonstrates typical tnef usage with a popular Unix mail client called "mutt".

  Step 1 -- Configure ~/.mailcap
Mutt can't use tnef for its intended purpose until an appropriate content type definition exists in ~/.mailcap . Here's a sample definition:

    application/ms-tnef; tnef -w %s

This mailcap entry says that whenever the MIME content type:

    application/ms-tnef

is encountered, use this command to decode it:

    tnef -w %s

The latter command string invokes tnef, specifying both the -w option and the attachment (created as a temporary file) as command line arguments.

  Step 2 -- Add The Filter To $PATH
Mutt can't invoke tnef if the filter isn't accessible via $PATH.

  Step 3 -- Test Mutt
Use mutt to read a message that includes a TNEF attachment. Mutt will note that an attachment of type "application/ms-tnef is unsupported".

Press the "v" key to open mutt's "view attachment" menu.

Move the cursor over the TNEF attachment and press the enter key to "view" the attachment. Mutt will launch tnef and invoke it using the command line syntax specified in ~/.mailcap (step 1). tnef then decodes all file(s) included in the TNEF attachment, prompting for confirmation prior to creating an individual file (refer to -w option above). -w is useful here because it gives the end user a chance to view the filename(s) included in the mail message.

Note that Mutt's attachment menu also supports a pipe option, which permits the user to pipe attachments to an external filter (how convenient). So, to list the contents of a TNEF attachment prior to decoding it, press the "|" key and enter this command:

    tnef -t

SEE ALSO
metamail(1), mailcap(4), mutt(1), other email clients.

AUTHOR
Mark Simpson.

REPORTING BUGS
Report bugs to Mark Simpson <damned@world.std.com> .

OTHER REFERENCES
This web page:

http://support.microsoft.com/support/kb/articles/Q136/2/04.asp

describes how to configure Microsoft email clients so that the TNEF format is disabled when sending messages to non-TNEF-compatible clients.