#ifndef _LINUX_IPC_H#define _LINUX_IPC_H#include <linux/types.h>typedef int key_t; 		/* should go in <types.h> type for IPC key */#define IPC_PRIVATE ((key_t) 0)  struct ipc_perm{  key_t  key;  ushort uid;   /* owner euid and egid */  ushort gid;  ushort cuid;  /* creator euid and egid */  ushort cgid;  ushort mode;  /* access modes see mode flags below */  ushort seq;   /* sequence number */};/* resource get request flags */#define IPC_CREAT  00001000   /* create if key is nonexistent */#define IPC_EXCL   00002000   /* fail if key exists */#define IPC_NOWAIT 00004000   /* return error on wait *//*  * Control commands used with semctl, msgctl and shmctl  * see also specific commands in sem.h, msg.h and shm.h */#define IPC_RMID 0     /* remove resource */#define IPC_SET  1     /* set ipc_perm options */#define IPC_STAT 2     /* get ipc_perm options */#define IPC_INFO 3     /* see ipcs */#ifdef __KERNEL__/* special shmsegs[id], msgque[id] or semary[id]  values */#define IPC_UNUSED	((void *) -1)#define IPC_NOID	((void *) -2)		/* being allocated/destroyed *//*  * These are used to wrap system calls. See ipc/util.c, libipc.c  */struct ipc_kludge {    struct msgbuf *msgp;    long msgtyp;};#define SEMOP	 	1#define SEMGET 		2#define SEMCTL 		3#define MSGSND 		11#define MSGRCV 		12#define MSGGET 		13#define MSGCTL 		14#define SHMAT 		21#define SHMDT 		22#define SHMGET 		23#define SHMCTL 		24#endif /* __KERNEL__ */#endif /* _LINUX_IPC_H */