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CMP(1)                      General Commands Manual                     CMP(1)

NAME
     cmp - compare two files

SYNOPSIS
     cmp [-c] [-l | -s] file1 file2 [skip1 [skip2]]

DESCRIPTION
     The cmp utility compares two files of any type and writes the results to
     the standard output.  By default, cmp is silent if the files are the
     same; if they differ, the byte and line number at which the first
     difference occurred is reported.

     Bytes and lines are numbered beginning with one.

     The following options are available:

     -c    Do the compare using getc(3) rather than mmap(2).  Combined with
           the -l flag, this can be helpful in locating an I/O error in the
           underlying device.

     -l    Print the byte number (decimal) and the differing byte values
           (octal) for each difference.

     -s    Print nothing for differing files; return exit status only.

     The optional arguments skip1 and skip2 are the byte offsets from the
     beginning of file1 and file2, respectively, where the comparison will
     begin.  The offset is decimal by default, but may be expressed as an
     hexadecimal or octal value by preceding it with a leading ``0x'' or
     ``0''.

EXIT STATUS
     The cmp utility exits with one of the following values:

     0     The files are identical.

     1     The files are different; this includes the case where one file is
           identical to the first part of the other.  In the latter case, if
           the -s option has not been specified, cmp writes to standard output
           that EOF was reached in the shorter file (before any differences
           were found).

     >1    An error occurred.

SEE ALSO
     comm(1), diff(1), diff3(1), sdiff(1)

STANDARDS
     The cmp utility is expected to be IEEE Std 1003.2 ("POSIX.2") compatible.

HISTORY
     The cmp utility first appeared in Version 1 AT&T UNIX.

NetBSD 10.99                   December 13, 2016                  NetBSD 10.99