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wc(1)



sum(1)                           DG/UX 5.4.2                          sum(1)


NAME
       sum - print checksum and block count of a file

SYNOPSIS
       sum [ -r ] file

DESCRIPTION
       Sum calculates and prints a 16-bit checksum for the named file, and
       also prints the number of blocks in the file.  It is typically used
       to look for bad spots, or to validate a file communicated over some
       transmission line.  The option -r causes an alternate algorithm to be
       used in computing the checksum.

EXAMPLES
       sum record

       Prints the file name and checksum for "record", and the number of 512
       byte blocks of disk space that "record" occupies.  If you transmit
       "record" to another system and then execute sum again, you can check
       that "record" was transmitted without any errors.

       sum -r record labels

       Calculates the checksum and the number of 512 byte blocks of disk
       space for the files "record" and "labels".  You use the alternate
       algorithm because "record" and "label" were transferred to your
       system from a UNIX System Version 7 system.  The algorithm used with
       the -r option is compatible with the algorithm used by sum on UNIX
       System Version 7 systems.  This allows you to compare the checksum
       values both before and after the files were transmitted to check that
       there are no errors.  Sum prints the information for each file on a
       separate line.

       grep -l account /SYSTEMS/* | xargs sum

       Grep(1) searches through the directory "SYSTEMS" for files with the
       string "account" in them.  The command xargs(1) passes each file
       found as an argument.  Sum prints a checksum, the number of 512 byte
       blocks of disk space, and the file name of each file.  This command
       is useful for checking that many files transferred without errors
       from one system to another.

DIAGNOSTICS
       "Read error" is indistinguishable from end of file on most devices;
       check the block count.

SEE ALSO
       wc(1).









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