emacs/lib/cloexec.h
Paul Eggert 794c3cd3a2 Merge from Gnulib; use ‘open’ for O_CLOEXEC
This incorporates:
2017-08-15 renameat: ensure declaration in <stdio.h> on NetBSD
2017-08-15 extensions: enable NetBSD specific extensions
2017-08-14 open: support O_CLOEXEC
2017-08-13 reallocarray: new module
* admin/merge-gnulib (AVOIDED_MODULES): Remove ‘open’, since
it now supports O_CLOEXEC and this simplifies Emacs.
* build-aux/config.guess, lib/fcntl.in.h, lib/stdio.in.h:
* lib/stdlib.in.h, m4/extensions.m4, m4/stdlib_h.m4:
Copy from Gnulib.
* lib/cloexec.c, lib/cloexec.h, lib/open.c:
* m4/mode_t.m4, m4/open-cloexec.m4, m4/open.m4:
New files, copied from Gnulib.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.
* lib-src/etags.c (O_CLOEXEC) [WINDOWSNT]:
Remove, as Gnulib does this for us.
* src/filelock.c (create_lock_file):
* src/sysdep.c (emacs_open, emacs_pipe):
Don’t worry about O_CLOEXEC == 0, as Gnulib no longer sets it to 0.
2017-08-16 14:04:33 -07:00

38 lines
1.5 KiB
C

/* cloexec.c - set or clear the close-on-exec descriptor flag
Copyright (C) 2004, 2009-2017 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdbool.h>
/* Set the 'FD_CLOEXEC' flag of DESC if VALUE is true,
or clear the flag if VALUE is false.
Return 0 on success, or -1 on error with 'errno' set.
Note that on MingW, this function does NOT protect DESC from being
inherited into spawned children. Instead, either use dup_cloexec
followed by closing the original DESC, or use interfaces such as
open or pipe2 that accept flags like O_CLOEXEC to create DESC
non-inheritable in the first place. */
int set_cloexec_flag (int desc, bool value);
/* Duplicates a file handle FD, while marking the copy to be closed
prior to exec or spawn. Returns -1 and sets errno if FD could not
be duplicated. */
int dup_cloexec (int fd);