# mcrypt_get_block_size

(PHP 4, PHP 5)

mcrypt_get_block_size — Get the block size of the specified cipher

### Description

int mcrypt_get_block_size ( int `$cipher` )
int mcrypt_get_block_size ( string `$cipher` , string `$module` )

The first prototype is when linked against libmcrypt 2.2.x, the second when linked against libmcrypt 2.4.x or 2.5.x.

mcrypt_get_block_size() is used to get the size of a block of the specified `cipher` (in combination with an encryption mode).

It is more useful to use the mcrypt_enc_get_block_size() function as this uses the resource returned by mcrypt_module_open().

This example shows how to use this function when linked against libmcrypt 2.4.x and 2.5.x.

Example#1 mcrypt_get_block_size() example

`<?php
echo mcrypt_get_block_size('tripledes', 'ecb');
?>
Prints:
8`

See also: mcrypt_get_key_size(), mcrypt_enc_get_block_size() and mcrypt_encrypt().