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)
