MD5SUM(1)

NAME
md5sum - generate/check MD5 message digests

SYNOPSIS
md5sum [-bv] [-c [ file ] ]
md5sum file ...

DESCRIPTION
md5sum generates and checks MD5 message digests, as described in RFC-1321. The "message digest" produced can be thought of as a 128-bit "signature" of the input file. Typically, md5sum is used to verify the integrity of files made available for distribution via anonymous ftp (for example, announcements for new versions of irc(1) usually contain MD5 signatures).

Message digests for a tree of files can be generated with a command similar to the following:

    find . -type f -print | xargs md5sum

The output of this command is suitable as input for the -c option.

OPTIONS

-c [file]
    Check message digests. Input is taken from stdin or from the spcified file. The input should be in the same format as the output generated by md5sum.

-v  Verbose. Print file names when checking.

-b  Read files in binary mode (otherwise, end-of-file conventions will be ignored).

HISTOY
The md5sum program was written by Branko Lankester and may be freely distributed. The original source code is in the MIT PGP 2.6.2 distribution. Those concerned about the integrity of this version should obtain the original sources and compile their own version.

The underlying implementation of Ron Rivest's MD5 algorithm was written by Colin Plumb and is in the Public Domain. (Equivalent code is also available from RSA Data Security, Inc.)

SEE ALSO
sum(1), cksum(1), pgp(1)