Deal with lack of O_CLOEXEC
Deal with lack of O_CLOEXEC

Some platforms don't have it. We fall back to fcntl() in other
places, so do it here as well.

https://bugzilla.gnome.org/show_bug.cgi?id=769042

johne53/MB3Glib,endlessm/glib,johne53/MB3Glib,johne53/MB3Glib,endlessm/glib,endlessm/glib,endlessm/glib,johne53/MB3Glib,johne53/MB3Glib,endlessm/glib,johne53/MB3Glib