mcrypt_list_algorithms Get an array of all supported ciphers arraymcrypt_list_algorithms string lib_dir mcrypt_list_algorithms is used to get an array of all supported algorithms in the lib_dir. mcrypt_list_algorithms takes as optional parameter a directory which specifies the directory where all algorithms are located. If not specifies, the value of the mcrypt.algorithms_dir &php.ini; directive is used. ]]> The above example will produce a list with all supported algorithms in the "/usr/local/lib/libmcrypt" directory.