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<mcrypt_module_is_block_algorithmmcrypt_module_is_block_mode>
^Mcrypt FunctionsLast updated: Mon, 26 Oct 2026

mcrypt_module_is_block_algorithm_mode

(PHP 4 >= 4.0.2, PHP 5, PHP 7 < 7.2.0, PECL mcrypt >= 1.0.0)

mcrypt_module_is_block_algorithm_mode — Returns if the specified module is a block algorithm or not

Warning

This function has been DEPRECATED as of PHP 7.1.0 and REMOVED as of PHP 7.2.0. Relying on this function is highly discouraged.

Description

function mcrypt_module_is_block_algorithm_mode(string $mode, string $lib_dir = ?): bool

This function returns true if the mode is for use with block algorithms, otherwise it returns false. (e.g. false for stream, and true for cbc, cfb, ofb).

Parameters

mode

The mode to check.

lib_dir

The optional lib_dir parameter can contain the location where the algorithm module is on the system.

Return Values

This function returns true if the mode is for use with block algorithms, otherwise it returns false. (e.g. false for stream, and true for cbc, cfb, ofb).


<mcrypt_module_is_block_algorithmmcrypt_module_is_block_mode>
^Mcrypt FunctionsLast updated: Mon, 26 Oct 2026