shasum(1)

 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
       --tag         create a BSD-style checksum
   -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
 The following five options are useful only when verifying checksums:
       --ignore-missing  don't fail or report status for missing files
   -q, --quiet           don't print OK for each successfully verified file
   -s, --status          don't output anything, status code shows success
       --strict          exit non-zero for improperly formatted checksum lines
   -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),
 and name for each FILE.  The line starts with a `\' character if the
 FILE name contains either newlines or backslashes, which are then
 replaced by the two-character sequences `\n' and `\\' respectively.
 Report shasum bugs to [email protected]

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

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

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