shasum Man page

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

NAME

shasum – Print or Check SHA Checksums

SYNOPSIS

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

-a, –algorithm 1 (default), 224, 256, 384, 512, 512224, 512256
-b, –binary read in binary mode
-c, –check read SHA sums from the FILEs and check them
-t, –text read in text mode (default)
-U, –UNIVERSAL read in Universal Newlines mode
produces same digest on Windows/Unix/Mac
-0, –01 read in BITS mode
ASCII ‘0’ interpreted as 0-bit,
ASCII ‘1’ interpreted as 1-bit,
all other characters ignored
-p, –portable read in portable mode (to be deprecated)

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 checksum lines

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

When verifying SHA-512/224 or SHA-512/256 checksums, indicate the
algorithm explicitly using the -a option, e.g.

shasum -a 512224 -c checksumfile

The sums are computed as described in FIPS PUB 180-4. 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, `U’ for UNIVERSAL, `^’ for BITS, `?’
for portable), and name for each FILE.

Report shasum bugs to mshelor@cpan.org

DESCRIPTION

Running shasum is often the quickest way to compute SHA message
digests. The user simply feeds data to the script through files or
standard input, and then collects the results from standard output.

The following command shows how to compute digests for typical inputs
such as the NIST test vector “abc”:

perl -e “print qq(abc)” | shasum

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

perl -e “print qq(abc)” | shasum -a 256

Since shasum mimics the behavior of the combined GNU sha1sum,
sha224sum, sha256sum, sha384sum, and sha512sum programs, you can
install this script as a convenient drop-in replacement.

Unlike the GNU programs, shasum encompasses the full SHA standard by
allowing partial-byte inputs. This is accomplished through the BITS
option (-0). The following example computes the SHA-224 digest of the
7-bit message 0001100:

perl -e “print qq(0001100)” | shasum -0 -a 224

AUTHOR

Copyright (c) 2003-2015 Mark Shelor .

SEE ALSO

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

perl v5.22.1 2016-03-13 SHASUM(1)