mcrypt_enc_is_block_mode
    (PHP 4 >= 4.0.2, PHP 5)
mcrypt_enc_is_block_mode -- Checks whether the opened mode outputs blocks
Description
bool 
mcrypt_enc_is_block_mode ( resource td )
     This function returns TRUE if the mode outputs blocks of bytes or
     FALSE if it outputs bytes. (e.g. TRUE for cbc and ecb, and FALSE for cfb and
     stream).