cmp.1

<B>Digital的Unix操作系统VAX 4.2源码</B>

.TH cmp 1
.SH Name
cmp \- compare two files
.SH Syntax
.B cmp
[\fB\-l\fR | \fB\-s\fR] \fIfile1 file2\fR  [ \fIskip1\fR ]  [ \fIskip2\fR ]
.SH Description
.NXR "cmp command"
.NXR "file" "comparing"
.NXR "comparing files with cmp"
The
.PN cmp
command compares two files. 
If either
.I file1
or
.I file2
is `\-',
standard input is used for the file.
With no options,
.PN cmp
makes no comment if the files are the same.
If they differ, it reports the byte and line number
at which the difference occurred to standard output.
If one file is an initial subsequence
of the other a message including the file name is written to
standard error.  
.PP
The optional
.I skip1
and
.I skip2
parameters are initial byte offsets into
.I file1
and
.I file2
respectively and may be either octal, by specifying a leading 0,
or decimal.  When using
.I skip1
and
.I skip2
the offset is treated as the start of the respective input file.
Only one option may be specified at a time.  Only one of the input
files may be standard input at a time.  Because the line number
is not calculated when using either of the options the use of either
flag will increase the speed of
.PN cmp .
.SH Options
.IP \fB\-l\fR 0.3i
Long format:  prints the byte number (decimal) and the differing
bytes (octal) for each difference.
.IP \fB\-s\fR 0.3i
Suppresses normal output and sets the exit code
only.
.SH Diagnostics
Exit code 0 is returned for identical
files, 1 for different files, and 2 for an
inaccessible or missing argument.
.SH See Also
comm(1), diff(1)