plan9 man page for sum

SUM(1)							      General Commands Manual							    SUM(1)

NAME
       sum, md5sum - sum and count blocks in a file

SYNOPSIS
       sum [ -5r ] [ file ...  ]

       md5sum [ file ...  ]

DESCRIPTION
       By default, sum calculates and prints a 32-bit hexadecimal checksum, a byte count, and the name of each file.  The checksum is also a func-
       tion of the input length.  If no files are given, the standard input is summed.	Other summing algorithms are available.  The options are

       -r     Sum with the algorithm of System V's sum -r and print the length (in 1K blocks) of the input.

       -5     Sum with System V's default algorithm and print the length (in 512-byte blocks) of the input.

       Sum is typically used to look for bad spots, to validate a file communicated over some transmission line or as a quick way to determine	if
       two files on different machines might be the same.

       Md5sum  computes  the  32  hex digit RSA Data Security, Inc. MD5 Message-Digest Algorithm described in RFC1321.	If no files are given, the
       standard input is summed.

SOURCE
       /sys/src/cmd/sum.c
       /sys/src/cmd/md5sum.l

SEE ALSO
       cmp(1), wc(1)

																	    SUM(1)