Do not accept control from stdin when running in the background

		fdsize = xfd + 1;

		pt = feh_get_time();

		first = 0;

		if (isatty(STDIN_FILENO) && !opt.multiwindow) {

		/*

		 * Only accept commands from stdin if

		 * - stdin is a terminal (otherwise it's probably used as an image / filelist)

		 * - we aren't running in multiwindow mode (cause it's not clear which

		 *   window commands should be applied to in that case)

		 * - we're in the same process group as stdin, AKA we're not running

		 *   in the background. Background processes are stopped with SIGTTOU

		 *   if they try to write to stdout or change terminal attributes. They

		 *   also don't get input from stdin anyway.

		 */

		if (isatty(STDIN_FILENO) && !opt.multiwindow && getpgrp() == (tcgetpgrp(STDIN_FILENO))) {

			control_via_stdin = 1;

			struct termios ctrl;

			if (tcgetattr(STDIN_FILENO, &old_term_settings) == -1)