Section: Perl Programmers Reference Guide (1)

Updated: 2016-01-15

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shasum - Print or Check SHA Checksums


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) -p, --portable read in portable 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

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, `?' for portable, `^' for BITS), and name for each FILE.

Report shasum bugs to [email protected]



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'':

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

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:


Copyright (c) 2003-2014 Mark Shelor <[email protected]>.


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







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