1 /* Copyright (C) 1995-2021 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_SEM_H 19 # error "Never include <bits/sem.h> directly; use <sys/sem.h> instead." 20 #endif 21 22 #include <sys/types.h> 23 24 /* Flags for `semop'. */ 25 #define SEM_UNDO 0x1000 /* undo the operation on exit */ 26 27 /* Commands for `semctl'. */ 28 #define GETPID 11 /* get sempid */ 29 #define GETVAL 12 /* get semval */ 30 #define GETALL 13 /* get all semval's */ 31 #define GETNCNT 14 /* get semncnt */ 32 #define GETZCNT 15 /* get semzcnt */ 33 #define SETVAL 16 /* set semval */ 34 #define SETALL 17 /* set all semval's */ 35 36 37 /* Data structure describing a set of semaphores. */ 38 struct semid_ds 39 { 40 struct ipc_perm sem_perm; /* operation permission struct */ 41 __time_t sem_otime; /* last semop() time */ 42 __time_t sem_ctime; /* last time changed by semctl() */ 43 struct sem *__sembase; /* ptr to first semaphore in array */ 44 struct __sem_queue *__sem_pending; /* pending operations */ 45 struct __sem_queue *__sem_pending_last;/* last pending operation */ 46 struct __sem_undo *__undo; /* ondo requests on this array */ 47 unsigned short int sem_nsems; /* number of semaphores in set */ 48 }; 49 50 51 /* The user should define a union like the following to use it for arguments 52 for `semctl'. 53 54 union semun 55 { 56 int val; <= value for SETVAL 57 struct semid_ds *buf; <= buffer for IPC_STAT & IPC_SET 58 unsigned short int *array; <= array for GETALL & SETALL 59 struct seminfo *__buf; <= buffer for IPC_INFO 60 }; 61 62 Previous versions of this file used to define this union but this is 63 incorrect. One can test the macro _SEM_SEMUN_UNDEFINED to see whether 64 one must define the union or not. */ 65 #define _SEM_SEMUN_UNDEFINED 1 66 67 #ifdef __USE_MISC 68 69 /* ipcs ctl cmds */ 70 # define SEM_STAT 18 71 # define SEM_INFO 19 72 73 struct seminfo 74 { 75 int semmap; 76 int semmni; 77 int semmns; 78 int semmnu; 79 int semmsl; 80 int semopm; 81 int semume; 82 int semusz; 83 int semvmx; 84 int semaem; 85 }; 86 87 #endif /* __USE_MISC */ 88