SUM(1) SUM(1)
NAME
sum - sum and count blocks in a file
SYNOPSIS
sum [ -5r ] [ file ... ]
DESCRIPTION
By default, sum calculates and prints a 32-bit hexadecimal
checksum, a byte count and the name of each file. The check-
sum is also a function of the input length. If no files are
given, the standard input is summed. Other summing algo-
rithms 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.
SEE ALSO
cmp(1), wc(1)
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