1 /* Copyright (C) 1995-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #ifndef _SYS_IPC_H
19 # error "Never use <bits/ipc.h> directly; include <sys/ipc.h> instead."
20 #endif
21 
22 #include <bits/types.h>
23 
24 /* Mode bits for `msgget', `semget', and `shmget'.  */
25 #define IPC_CREAT	01000		/* create key if key does not exist */
26 #define IPC_EXCL	02000		/* fail if key exists */
27 #define IPC_NOWAIT	04000		/* return error on wait */
28 
29 /* Control commands for `msgctl', `semctl', and `shmctl'.  */
30 #define IPC_RMID	0		/* remove identifier */
31 #define IPC_SET		1		/* set `ipc_perm' options */
32 #define IPC_STAT	2		/* get `ipc_perm' options */
33 
34 /* Special key values.  */
35 #define IPC_PRIVATE	((key_t) 0)	/* private key */
36 
37 
38 /* Data structure used to pass permission information to IPC operations.  */
39 struct ipc_perm
40   {
41     __uid_t uid;			/* owner's user ID */
42     __gid_t gid;			/* owner's group ID */
43     __uid_t cuid;			/* creator's user ID */
44     __gid_t cgid;			/* creator's group ID */
45     __mode_t mode;			/* read/write permission */
46   };
47