cmp Man page

CMP(1) User Commands CMP(1)


cmp – compare two files byte by byte




Compare two files byte by byte.

The optional SKIP1 and SKIP2 specify the number of bytes to skip at the
beginning of each file (zero by default).

Mandatory arguments to long options are mandatory for short options

-b, –print-bytes
print differing bytes

-i, –ignore-initial=SKIP
skip first SKIP bytes of both inputs

-i, –ignore-initial=SKIP1:SKIP2
skip first SKIP1 bytes of FILE1 and first SKIP2 bytes of FILE2

-l, –verbose
output byte numbers and differing byte values

-n, –bytes=LIMIT
compare at most LIMIT bytes

-s, –quiet, –silent
suppress all normal output

–help display this help and exit

-v, –version
output version information and exit

SKIP values may be followed by the following multiplicative suffixes:
kB 1000, K 1024, MB 1,000,000, M 1,048,576, GB 1,000,000,000, G
1,073,741,824, and so on for T, P, E, Z, Y.

If a FILE is `-‘ or missing, read standard input. Exit status is 0 if
inputs are the same, 1 if different, 2 if trouble.


Written by Torbjorn Granlund and David MacKenzie.


Report bugs to:
GNU diffutils home page:
General help using GNU software:


Copyright © 2011 Free Software Foundation, Inc. License GPLv3+: GNU
GPL version 3 or later .
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.


diff, diff3, sdiff

The full documentation for cmp is maintained as a Texinfo manual. If
the info and cmp programs are properly installed at your site, the com‐

info cmp

should give you access to the complete manual.

diffutils 3.3 March 2013 CMP(1)