commit d72f691c0c9cace857975a6608a4cb431c8b6846
 Author: Keith Packard <keithp@keithp.com>
 Date:   Fri Apr 18 15:00:30 2014 -0700

    os: FatalError if -displayfd writes fail

    When the server is started with the -displayfd option, check to make
    sure that the writes succeed and give up running if they don't.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jamey Sharp <jamey@minilop.net>

 commit 4957e986841225e9984daca76f1a0ee08df125bb
 Author: Keith Packard <keithp@keithp.com>
 Date:   Fri Apr 18 15:00:35 2014 -0700

    os: Clear the -displayfd option after closing the file

    Failing to clear this means that we'll attempt to write the display
    number to a random file descriptor on subsequent X server generations.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Jamey Sharp <jamey@minilop.net>
Backported-to-NX-by: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>