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SHASUM(1)              Perl Programmers Reference Guide              SHASUM(1)



NAME
       shasum - Print or Check SHA Checksums

SYNOPSIS
        Usage: shasum [OPTION] [FILE]...
           or: shasum [OPTION] --check [FILE]
        Print or check SHA checksums.
        With no FILE, or when FILE is -, read standard input.

         -a, --algorithm    1 (default), 224, 256, 384, 512
         -b, --binary       read files in binary mode (default on DOS/Windows)
         -c, --check        check SHA sums against given list
         -p, --portable     read files in portable mode
                                produces same digest on Windows/Unix/Mac
         -t, --text         read files in text mode (default)

        The following two options are useful only when verifying checksums:

         -s, --status       don't output anything, status code shows success
         -w, --warn         warn about improperly formatted SHA checksum lines

         -h, --help         display this help and exit
         -v, --version      output version information and exit

        The sums are computed as described in FIPS PUB 180-2.  When checking,
        the input should be a former output of this program.  The default mode
        is to print a line with checksum, a character indicating type (`*'
        for binary, `?' for portable, ` ' for text), and name for each FILE.

DESCRIPTION
       The shasum script provides the easiest and most convenient way to
       compute SHA message digests.  Rather than writing a program, the user
       simply feeds data to the script via the command line, and waits for the
       results to be printed on standard output.  Data can be fed to shasum
       through files, standard input, or both.

       The following command shows how easy it is to compute digests for
       typical inputs such as the NIST test vector "abc":

               perl -e "print qw(abc)" | shasum

       Or, if you want to use SHA-256 instead of the default SHA-1, simply
       say:

               perl -e "print qw(abc)" | shasum -a 256

       Since shasum uses the same interface employed by the familiar sha1sum
       program (and its somewhat outmoded anscestor md5sum), you can install
       this script as a convenient drop-in replacement.

AUTHOR
       Copyright (c) 2003-2008 Mark Shelor <mshelor@cpan.org>.

SEE ALSO
       shasum is implemented using the Perl module Digest::SHA or
       Digest::SHA::PurePerl.



perl v5.10.1                      2014-02-04                         SHASUM(1)