Computer Science
MUNPACK(1) MUNPACK(1)
NAME
munpack - unpack messages in MIME or split-uuencode format
SYNOPSIS
munpack [ -f ] [ -q ] [ -t ] [ -C directory ] [ filename
... ]
DESCRIPTION
The munpack program reads each RFC-822 message filename
and writes all non-text MIME parts or split-uuencoded
files as files. If no filename argument is given, munpack
reads from standard input.
If the message suggests a file name to use for the imbed-
ded part, that name is cleaned of potential problem char-
acters and used for the output file. If the suggested
filename includes subdirectories, they will be created as
necessary. If the message does not suggest a file name,
the names "part1", "part2", etc are used in sequence.
If the imbedded part was preceded with textual informa-
tion, that information is also written to a file. The
file is named the same as the imbedded part, with any
filename extension replaced with ".desc".
OPTIONS
-f Force overwriting of existing files. If a message
suggests a file name of an existing file, the file
will be overwritten. Without this flag, munpack
appends ".1", ".2", etc to find a nonexistent file.
-q Be quiet. Supresses messages about saving partial
messages and about messages with no interesting
information.
-t Also write the text MIME parts of multipart mes-
sages as files. By default, text parts that do not
have a filename parameter do not get unpacked.
This option effectively disables the ".desc" file
feature for MIME messages.
-C directory
Change the current directory to directory before
reading any files. This is useful when invoking
munpack from a mail or news reader.
DECODING MIME
To decode a MIME message, first save it to a text file.
If possible, save it with all headers included. Munpack
can decode some MIME files when the headers are missing or
incomplete, other files it cannot decode without having
the information in the headers. In general, messages
which have a statement at the beginning that they are in
MIME format can be decoded without the headers. Messages
which have been split into multiple parts generally
require all headers in order to be reassembled and
decoded.
Some LAN-based mail systems and some mail providers
(including America Online, as of the writing of this docu-
ment) place the mail headers at the bottom of the message,
instead of at the top of the message. If you are having
problems decoding a MIME message on such a system, you
need to convert the mail back into the standard format by
removing the system's nonstandard headers and moving the
standard Internet headers at the top of the message (sepa-
rated from the message body with a blank line).
There must be exactly one message per file. Munpack can-
not deal with multiple messages in a single file, to
decode things correctly it must know when one message ends
and the next one begins.
To decode a message, run the command:
munpack file
where "file" is the name of the file containing the mes-
sage. More than one filename may be specified, munpack
will try to decode the message in each file. For more
information on ways to run munpack, see the section
"OPTIONS" above.
ENVIRONMENT
TMPDIR Directory to store temporary files. Default is
/tmp.
FILES
$TMPDIR/m-prts-$USER/
Directory used to store partial messages awaiting
reassembly.
1
Back to the index