* misc/daemon.c (daemon): Fail if !noclose and we cannot open the
real /dev/null device.
* sysdeps/generic/check_fds.c: Include device-nrs.h.
* sysdeps/generic/device-nrs.h: New file.
* sysdeps/unix/sysv/linux/device-nrs.h: New file.
* misc/Makefile (distribute): Add device-nrs.h.
* posix/wordexp.c (exec_comm_child): Likewise.
* locale/nl_langinfo.c: Allow use of file for __nl_langinfo_l
definition.