V10/man/man1/sum.1

.TH SUM 1
.CT 1 files
.SH NAME
sum, treesum \- sum and count blocks in a file
.SH SYNOPSIS
.B sum
[
.B -5ri
]
[
.I file ...
]
.PP
.B treesum
[
.I file ...
]
.SH DESCRIPTION
By default,
.I sum
calculates and prints a 32-bit checksum,
a byte count
and the name of
each
.IR file .
The checksum is also a function of the input length.
If no files are given,
the standard input is
summed.
Other summing algorithms are available.
The options are
.TP
.B -i
Read file names from standard input.
.TP
.B -r
Sum with the algorithm of System V's
.B "sum -r"
and print the length (in 1K blocks) of the input.
.TP
.B -5
Sum with System V's default algorithm
and print the length (in 512-byte blocks) of the input.
.PP
.I 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 might be the same.
.PP
.I Treesum
is similar to
.BR "sum -r" ,
except that if
.I file
is a directory, then
.I treesum
recursively descends it, summing all non-directories encountered.
If no files are given,
.IR treesum
recursively sums the current directory.
.SH "SEE ALSO"
.IR wc (1)