Content-type: text/html Man page of cmp

cmp

Section: User Commands (1)
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NAME

cmp - Compares two files  

SYNOPSIS

cmp [-l|-s] file1 file2


 

STANDARDS

Interfaces documented on this reference page conform to industry standards as follows:

cmp:  XPG4, XPG4-UNIX

Refer to the standards(5) reference page for more information about industry standards and associated tags.
 

OPTIONS

Prints the byte number (decimal) and the differing bytes (octal) for each difference. Does not print data for differing files; returns only an exit value.
 

OPERANDS

The path name of a file to be compared. The path name of a file to be compared.
 

DESCRIPTION

The cmp command compares two files.

If file1 or file2 is - (dash), standard input is used for that file. It is an error to specify - for both files.

By default, the cmp command prints no information if the files are the same. If the files differ, cmp prints the byte and line number where the difference occurred.

The cmp command also specifies whether one file is an initial subsequence of the other (that is, if the cmp command reads an End-of-File character in one file before finding any differences). Usually, you use the cmp command to compare nontext files and the diff command to compare text files.

Note that bytes and lines reported by cmp are numbered from 1.
 

EXIT STATUS

The following exit values are returned: The files are identical. The files differ. This includes files of different lengths that are identical in the first part of both files. An error occurred.
 

EXAMPLES

To determine whether two files are identical, enter: cmp prog.o.bak prog.o

The preceding command compares the files prog.o.bak and prog.o. If the files are identical, a message is not displayed. If the files differ, the location of the first difference is displayed. For instance: prog.o.bak prog.o differ: byte 5, line 1
If the message cmp: EOF on prog.o.bak is displayed, then the first part of prog.o is identical to prog.o.bak, but there is additional data in prog.o.
If the message cmp: EOF on prog.o is displayed, it is prog.o.bak that is the same as prog.o but also contains addition data. To display each pair of bytes that differ, enter: cmp -l prog.o.bak prog.o
This compares the files and then displays the byte number (in decimal) and the differing bytes (in octal) for each difference. For example, if the fifth byte is octal 101 in prog.o.bak and 141 in prog.o, then the cmp command displays: 5 101 141
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ENVIRONMENT VARIABLES

The following environment variables affect the execution of cmp: Provides a default value for the internationalization variables that are unset or null. If LANG is unset or null, the corresponding value from the default locale is used. If any of the internationalization variables contain an invalid setting, the utility behaves as if none of the variables had been defined. If set to a non-empty string value, overrides the values of all the other internationalization variables. Determines the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as opposed to multibyte characters in arguments). Determines the locale for the format and contents of diagnostic messages written to standard error. Determines the location of message catalogues for the processing of LC_MESSAGES.
 

SEE ALSO

Commands:  comm(1), bdiff(1), diff(1), diff3(1), sdiff(1)

Standards:  standards(5)


 

Index

NAME
SYNOPSIS
STANDARDS
OPTIONS
OPERANDS
DESCRIPTION
EXIT STATUS
EXAMPLES
ENVIRONMENT VARIABLES
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 02:43:04 GMT, October 02, 2010