1  /* Copyright (C) 1995-2023 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    };