Package mcrypt

Replacement for crypt()

http://mcrypt.sourceforge.net/

MCrypt is a replacement for the old crypt() package and crypt(1) command,
with extensions. It allows developers to use a wide range of encryption
functions, without making drastic changes to their code. It allows users
to encrypt files or data streams without having to be cryptographers.

General Commands (Section 1)
mcrypt
Mcrypt is a simple crypting program, a replacement for the old unix crypt(1). When encrypting or decrypting a file, a new file is created with the extension .nc...