cmp

Overview ¶

cmp compares two files and prints a message if their contents differ.

Synopsis:

cmp [–lLs] FILE1 FILE2 [OFFSET1 [OFFSET2]]

Description:

If offsets are given, comparison starts at the designated byte position
of the corresponding file.

Offsets that begin with 0x are hexadecimal; with 0, octal; with anything
else, decimal.

Options:

–l: Print the byte number (decimal) and the differing bytes (octal) for
    each difference.
–L: Print the line number of the first differing byte.
–s: Print nothing for differing files, but set the exit status.

What is an error, what goes on stderr, and what goes on stdout in cmp is fairly ad-hoc, but go something like this: invocation error: unparseable integer: error return from cmp() IO error, file too small: output on stderr, error return from cmp() Files are different: print difference info on stdout, no error return Files are same: no output, no error