Calculates an md5 checksum value of the text provided in
files, or from standard input. By default, when
files is given,
md5 prints those values first, followed by the checksum.
Calculate a checksum of the text in
Print the standard input followed by the checksum.
Operate in quiet mode. Print only the checksum.
Reverse the order of the output when string or files is given (checksum first).
Run the built-in speed test, which calculates a checksum from 100 MB of data.
Run the built-in test suite, which calculates checksums from seven short strings.