Mcrypt Functions
PHP Manual

mcrypt_enc_is_block_mode

Checks whether the opened mode outputs blocks

Warning

This function has been DEPRECATED as of PHP 7.1.0. Relying on this function is highly discouraged.

Description

bool mcrypt_enc_is_block_mode ( resource $td )

Tells whether the opened mode outputs blocks (e.g. TRUE for cbc and ecb, and FALSE for cfb and stream).

Parameters

td

The encryption descriptor.

Return Values

Returns TRUE if the mode outputs blocks of bytes, or FALSE if it outputs just bytes.