/**
 * Method to install a signal handler.
 *
 * @param   integer   $signal   The signal number.
 * @param   callable  $handler  The signal handler which may be the name of a user created function,
 *                              or method, or either of the two global constants SIG_IGN or SIG_DFL.
 * @param   boolean   $restart  Specifies whether system call restarting should be used when this
 *                              signal arrives.
 *
 * @return  boolean  True on success.
 *
 * @see     pcntl_signal()
 * @since   1.7.3
 */
protected function pcntlSignal($signal, $handler, $restart = true)
{
    return pcntl_signal($signal, $handler, $restart);
}