xref: /freebsd/usr.bin/cmp/cmp.1 (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
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35.\"     @(#)cmp.1	8.1 (Berkeley) 6/6/93
36.\" $FreeBSD$
37.\"
38.Dd December 19, 2006
39.Dt CMP 1
40.Os
41.Sh NAME
42.Nm cmp
43.Nd compare two files
44.Sh SYNOPSIS
45.Nm
46.Op Fl l | s | x
47.Op Fl hz
48.Ar file1 file2
49.Op Ar skip1 Op Ar skip2
50.Sh DESCRIPTION
51The
52.Nm
53utility compares two files of any type and writes the results
54to the standard output.
55By default,
56.Nm
57is silent if the files are the same; if they differ, the byte
58and line number at which the first difference occurred is reported.
59.Pp
60Bytes and lines are numbered beginning with one.
61.Pp
62The following options are available:
63.Bl -tag -width indent
64.It Fl h
65Do not follow symbolic links.
66.It Fl l
67Print the byte number (decimal) and the differing
68byte values (octal) for each difference.
69.It Fl s
70Print nothing for differing files; return exit
71status only.
72.It Fl x
73Like
74.Fl l
75but prints in hexadecimal and using zero as index
76for the first byte in the files.
77.It Fl z
78For regular files compare file sizes first, and fail the comparison if they
79are not equal.
80.El
81.Pp
82The optional arguments
83.Ar skip1
84and
85.Ar skip2
86are the byte offsets from the beginning of
87.Ar file1
88and
89.Ar file2 ,
90respectively, where the comparison will begin.
91The offset is decimal by default, but may be expressed as a hexadecimal
92or octal value by preceding it with a leading ``0x'' or ``0''.
93.Sh EXIT STATUS
94The
95.Nm
96utility exits with one of the following values:
97.Bl -tag -width 4n
98.It 0
99The files are identical.
100.It 1
101The files are different; this includes the case
102where one file is identical to the first part of
103the other.
104In the latter case, if the
105.Fl s
106option has not been specified,
107.Nm
108writes to standard error that EOF was reached in the shorter
109file (before any differences were found).
110.It >1
111An error occurred.
112.El
113.Sh SEE ALSO
114.Xr diff 1 ,
115.Xr diff3 1
116.Sh STANDARDS
117The
118.Nm
119utility is expected to be
120.St -p1003.2
121compatible.
122.Sh HISTORY
123A
124.Nm
125command appeared in
126.At v1 .
127