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sum(1)								       sum(1)



NAME

  sum -	Displays the checksum and byte count in	block-size (1024) units	of a
  file

SYNOPSIS

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

  The sum command reads	file and calculates a 16-bit checksum and the byte
  count	in block-size (1024) units 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:	XCU5.0

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

OPTIONS

  -o  [Tru64 UNIX]  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).

      [Tru64 UNIX]  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 commun-
  icated over transmission lines is an exact copy of the original. The sum
  command writes the space used	in 1024-byte units.

  [Tru64 UNIX]	The checksum is	calculated using a rigorous byte-byte compu-
  tation by default.






  System V Compatibility


  [Tru64 UNIX]	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

  The sum utility is marked LEGACY in XCU Issue	5.

   1.  [Tru64 UNIX]  The default algorithm is no longer	the word-by-word com-
       putation	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 multi-
      byte characters in arguments).

  LC_MESSAGES
      Determines the locale for	the format and contents	of diagnostic mes-
      sages 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)