NAME
    shasum - compute and check SHA1 message digest

SYNOPSIS
    sha1sum [OPTION] [FILE]...
    sha1sum [OPTION] --check [FILE]

DESCRIPTION
    Print or check SHA1 (160-bit) checksums.  With no FILE, or when FILE is
    -, read standard input.

    -b, --binary
    read files in binary mode (default on DOS/Windows)

    -c, --check
    check SHA1 sums against given list

    -t, --text
    read files in text mode (default)

  The following two options are useful only when verifying checksums:
    --status
    don't output anything, status code shows success

    -w, --warn
    warn about improperly formated checksum lines

    --help display this help and exit

    --version
    output version information and exit

    The sums are computed as described in FIPS-180-1. 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 text), and name for each FILE.

AUTHOR
    Written by Ulrich Drepper and Scott Miller.

REPORTING BUGS
    Report bugs to <bug-coreutils@gnu.org>.

COPYRIGHT
    Copyright (C) 2002 Free Software Foundation, Inc.
    This is free software; see the source for copying conditions. There is
    NO warranty; not even for MERCHANTABILITY or FITNESS FOR  A PARTICULAR
    PURPOSE.

SEE ALSO
    The full documentation  for shasum is maintained as a Texinfo manual.
    If the info and shasum programs are properly installed at your  site,
    the command

    info shasum

    should give you access to the complete manual.