Index for Section 1

Alphabetical listing for C

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cmp(1)
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:XCU5.0

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

OPTIONS
  -l  Prints the byte number (decimal) and the differing bytes (octal) for
      each difference.

  -s  Does not print data for differing files; returns only an exit value.

OPERANDS
  file1
      The path name of a file to be compared.

  file2
      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:

  0   The files are identical.

  1   The files differ.	 This includes files of different lengths that are
      identical in the first part of both files.

  >1  An error occurred.

EXAMPLES
   1.  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.

   2.  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
	     .
	     .
	     .

ENVIRONMENT VARIABLES
  The following environment variables affect the execution of cmp:

  LANG
      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.

  LC_ALL
      If set to a non-empty string value, overrides the values of all the
      other internationalization variables.

  LC_CTYPE
      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).

  LC_MESSAGES
      Determines the locale for the format and contents of diagnostic
      messages written to standard error.

  NLSPATH
      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 for Section 1

Alphabetical listing for C

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