????
Your IP : 3.15.221.165
/* sys/sem.h
Written by Conrad Scott <conrad.scott@dsl.pipex.com>
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#ifndef _CYGWIN_SEM_H
#define _CYGWIN_SEM_H
#include <cygwin/ipc.h>
#ifdef __cplusplus
extern "C"
{
#endif
/* Semaphore operation flags:
*/
#define SEM_UNDO 010000 /* Set up adjust on exit entry. */
/* Command definitions for the semctl () function:
*/
#define GETNCNT 0x3000 /* Get semncnt. */
#define GETPID 0x3001 /* Get sempid. */
#define GETVAL 0x3002 /* Get semval. */
#define GETALL 0x3003 /* Get all cases of semval. */
#define GETZCNT 0x3004 /* Get semzcnt. */
#define SETVAL 0x3005 /* Set semval. */
#define SETALL 0x3006 /* Set all cases of semval. */
#ifdef _KERNEL
#define SEM_STAT 0x3010 /* For ipcs(8). */
#define SEM_INFO 0x3011 /* For ipcs(8). */
#endif /* _KERNEL */
struct semid_ds
{
struct ipc_perm sem_perm; /* Operation permission structure. */
unsigned short sem_nsems; /* Number of semaphores in set. */
timestruc_t sem_otim; /* Last semop () time. */
timestruc_t sem_ctim; /* Last time changed by semctl (). */
#ifdef _KERNEL
struct sem *sem_base; /* pointer to first semaphore in set */
long sem_spare4[1];
#else
long sem_spare4[2];
#endif /* _KERNEL */
};
#define sem_otime sem_otim.tv_sec
#define sem_ctime sem_ctim.tv_sec
struct sembuf
{
unsigned short sem_num; /* Semaphore number. */
short sem_op; /* Semaphore operation. */
short sem_flg; /* Operation flags. */
};
#ifdef _KERNEL
/* Buffer type for semctl (IPC_INFO, ...) as used by ipcs(8).
*/
struct seminfo
{
int32_t semmni; /* Maximum number of unique semaphore
sets, system wide. */
int32_t semmns; /* Maximum number of semaphores,
system wide. */
int32_t semmsl; /* Maximum number of semaphores per
semaphore set. */
int32_t semopm; /* Maximum number of operations per
semop call. */
int32_t semmnu; /* Maximum number of undo structures,
system wide. */
int32_t semume; /* Maximum number of undo entries per
undo structure. */
int32_t semvmx; /* Maximum semaphore value. */
int32_t semaem; /* Maximum adjust-on-exit value. */
int32_t semmap; /* # of entries in semaphore map */
int32_t semusz; /* size in bytes of undo structure */
int32_t sem_spare[2];
};
/* Buffer type for semctl (SEM_INFO, ...) as used by ipcs(8).
*/
struct sem_info
{
long sem_ids; /* Number of allocated semaphore sets. */
long sem_num; /* Number of allocated semaphores. */
};
/* Permission flags */
#define SEM_A IPC_W /* alter permission */
#define SEM_R IPC_R /* read permission */
/* Internally used mode bits. */
#define SEM_ALLOC 01000 /* semaphore is allocated */
#endif /* _KERNEL */
#ifdef _KERNEL
/* According to SUSv3, "the fourth argument [to semctl()] is optional and
depends upon the operation requested. If required, it is of type
union semun, which the application shall explicitly declare:" */
union semun {
int val; /* value for SETVAL */
struct semid_ds *buf; /* buffer for IPC_STAT, IPC_SET */
unsigned short *array; /* array for GETALL, SETALL */
};
/* Therefore this union is only declared here if building internal code.
_KERNEL must not be defined in exernal applications! Declare union
semun explicitely as required by SUSv3, please. */
#endif /* _KERNEL */
int semctl (int semid, int semnum, int cmd, ...);
int semget (key_t key, int nsems, int semflg);
int semop (int semid, struct sembuf *sops, size_t nsops);
#ifdef __cplusplus
}
#endif
#endif /* _CYGWIN_SEM_H */