shasum (1)
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NAME
shasum - Print or Check SHA ChecksumsSYNOPSIS
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 computeSHA
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