The MD4 message-digest algorithm takes input of arbitrary length and produces a 128-bit "fingerprint" or "message digest" of the input.
The MD4 algorithm is faster but potentially weaker than the related MD5 algorithm.
A tcl-only implementation of MD4 is now part of tcllib. Documentation can be found at http://tcllib.sourceforge.net/doc/md4.html
Note: MD4 is considered obsolete and should not be used for new projects: MD4 to Historic Status .
% package require md4
1.0.4
% base64::encode [md4::md4 {}]
MdbP4NFq6TG3PFnX4MCJwA==
% md4::md4 -hex {}
31D6CFE0D16AE931B73C59D7E0C089C0
% base64::encode [md4::md4 a]
veUssx3jPkYkXgX729b7JA==
% md4::md4 -hex a
BDE52CB31DE33E46245E05FBDBD6FB24By default, md4::md4 produces binary output strings. The -hex option makes it produce output in a human-readable format, and it is also quite common to use base64-encoding as that is more compact.