--TEST-- mcrypt_create_iv https://bugs.php.net/bug.php?id=55169 --CREDIT-- Ryan Biesemeyer <ryan@yaauie.com> --SKIPIF-- <?php if (!extension_loaded("mcrypt")) print "skip"; ?> --FILE-- <?php for( $i=1; $i<=64; $i = $i*2 ){ echo 'Input: '. $i . PHP_EOL; $random = mcrypt_create_iv( $i, MCRYPT_DEV_URANDOM ); echo ' Length: ' . strlen( $random ) . PHP_EOL; echo ' Hex: '. bin2hex( $random ) . PHP_EOL; echo PHP_EOL; } ?> --EXPECTF-- Input: 1 Length: 1 Hex: %x Input: 2 Length: 2 Hex: %x Input: 4 Length: 4 Hex: %x Input: 8 Length: 8 Hex: %x Input: 16 Length: 16 Hex: %x Input: 32 Length: 32 Hex: %x Input: 64 Length: 64 Hex: %x