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                                                                   sum(1)



        _________________________________________________________________
        sum                                                       Command
        print checksum and block count of a file
        _________________________________________________________________


        SYNTAX

        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



        DG/UX 4.00                                                 Page 1
               Licensed material--property of copyright holder(s)





                                                                   sum(1)



        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.
        _________________________________________________________________


        SEE ALSO

        wc(1).


        DIAGNOSTICS

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







































        DG/UX 4.00                                                 Page 2
               Licensed material--property of copyright holder(s)



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