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sum(1)
NAME
  sum - Displays the checksum and block count of a file

SYNOPSIS
  sum [-o|-r] [file...]

  The sum command reads file and calculates a 16-bit checksum and the number
  of blocks in the file.  If the file argument is omitted, sum reads standard
  input.

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

  sum:	XPG4, XPG4-UNIX

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

OPTIONS
  -o  [DIGITAL]	 Uses an algorithm to compute the checksum using word-by-word
      computation.

  -r  Uses an alternate algorithm to compute the checksum (rigorous byte-by-
      byte computation rather than the word-by-word computation).  This is
      the default.

OPERANDS
  file
      The file for which a checksum is to be computed.	If this operand is
      omitted, standard input is used.

DESCRIPTION
  The checksum and number of blocks are written to standard output.  The sum
  command is generally used to determine if a file that was copied or
  communicated over transmission lines is an exact copy of the original. The
  sum command writes the space used in 512-byte units.

  System V Compatibility


  [DIGITAL]  The root of the directory tree that contains the commands
  modified for SVID 2 compliance is specified in the file /etc/svid2_path.
  You can use /etc/svid2_profile as the basis for, or to include in, your
  .profile.  The file /etc/svid2_profile reads /etc/svid2_path and sets the
  first entries in the PATH environment variable so that the modified SVID 2
  commands are found first.

  [DIGITAL]  The checksum algorithms for the default sum command and the SVID
  2 compliant sum command are reversed.	 The SVID 2 compliant sum command
  uses the word-by-word algorithm by default and uses the byte-by-byte
  algorithm if you specify the -r option on the command line.


NOTES
   1.  [DIGITAL]  The default algorithm is no longer the word-by-word
       computation algorithm.  It was changed to the 4.3BSD default
       algorithm.

   2.  The algorithms used may not be portable, that is, the same checksum
       may not be produced for the same input on different systems.  Portable
       applications should use cksum.

EXIT STATUS
  The following exit values are returned:

  0   Successful completion.

  >0  An error occurred.

EXAMPLES
  To display the checksum of datafile and the number of blocks in this file,
  enter:

       sum datafile

  If the checksum of datafile is 1605 and if the file contains 3 blocks, sum
  displays:

       1605 3 datafile

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

  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:  cksum(1), wc(1)


  Standards:  standards(5)