cmp - compare two files

cmp compares two files file1 and file2. cmp writes no output if the files are the same. By default, if the files differ, the byte and line number at which the first difference occurred are written to standard output. Bytes and lines are numbered beginning with 1.

If skip1 or skip2 are specified, or the -i option is specified, initial bytes of the corresponding file are skipped before beginning the compare. The skip values are in bytes or can have a suffix of k for kilobytes or m for megabytes.

If either file1 or files2 is -, cmp uses standard input starting at the current location.

-b, --print-bytes

Print differing bytes as 3 digit octal values.

-c, --print-chars

Print differing bytes as follows: non-space printable characters as themselves; space and control characters as ^ followed by a letter of the alphabet; and characters with the high bit set as the lower 7 bit character prefixed by M^ for 7 bit space and non-printable characters and M- for all other characters. If the 7 bit character encoding is not ASCII then the characters are converted to ASCII to determine high bit set, and if set it is cleared and converted back to the native encoding. Multibyte characters in the current locale are treated as printable characters.

-d, --differences=differences

Print at most differences differences using --verbose output format. --differences=0 is equivalent to --silent.

-i, --ignore-initial|skip=skip1[:skip2]

Skip the the first skip1 bytes in file1 and the first skip2 bytes in file2. If skip2 is omitted then skip1 is used. The default value is 0:0.

-l, --verbose

Write the decimal byte number and the differing bytes (in octal) for each difference.

-n, --count|bytes=count

Compare at most count bytes.

-s, --quiet|silent

Write nothing for differing files; return non-zero exit status only.

0

The files or portions compared are identical.

1

The files are different.

>1

An error occurred.

comm(1), diff(1), cat(1)

version

cmp (AT&T Research) 2010-04-11

author

Glenn Fowler <gsf@research.att.com>

author

David Korn <dgk@research.att.com>

copyright

Copyright © 1992-2012 AT&T Intellectual Property

license

http://www.eclipse.org/org/documents/epl-v10.html