public static function ivsize(string $cipher): int
    {
        $ret = \openssl_cipher_iv_length($cipher);

        if ($ret === false) {
            throw new \Exception("Failed to determine correct IV size.");
        }

        return $ret;
    }
public static function ivsize(string $cipher): int
    {
        $ret = \openssl_cipher_iv_length($cipher);

        if ($ret === false) {
            throw new \Exception("Failed to determine correct IV size.");
        }

        return $ret;
    }
public static function ivsize ( string $ cipher ) : int { $ ret = \ openssl_cipher_iv_length ( $ cipher ) ; if ( $ ret === false ) { throw new \ Exception ( "Failed to determine correct IV size." ) ; } return $ ret ; }
Get IV size for specified CIPHER.

@param string $cipher
@return int
@throws \Exception
Get IV size for specified CIPHER .