Coherent4.2.10/include/sys/shm.h

/* (-lgl
 *	Coherent 386 release 4.2
 *	Copyright (c) 1982, 1993 by Mark Williams Company.
 *	All rights reserved. May not be copied without permission.
 *	For copying permission and licensing info, write licensing@mwc.com
 -lgl) */

#ifndef __SYS_SHM_H__
#define	__SYS_SHM_H__

/*
 * Shared memory support.
 */

#include <common/feature.h>
#include <common/ccompat.h>
#include <common/__pid.h>
#include <common/__time.h>
#include <common/_ipcperm.h>
#include <common/_imode.h>


/*
 * ipc_perm Mode Definitions.
 */

#define	SHM_CLEAR	0x0200	/* clear segment on next attach */
#define	SHM_DEST	0x0400	/* destroy segment when # attached = 0 */


/*
 * Message Operations Flags.
 */

#define	SHM_RDONLY	010000	/* attach read-only (else read-write) */
#define SHM_RND		020000	/* round attach address to SHMLBA */


/* 
 * Shared memory control operations (are not included in iBCS2)
 * COHERENT 4.0.x does not use a swapper.
 */

#define	SHM_LOCK	3	/* lock shared memory segment in core */
#define SHM_UNLOCK	4	/* unlock shared memory segment */


/*
 * There is a shared mem id data structure for each segment in the system.
 */

#if	_SYSV4

struct shmid_ds {
	struct ipc_perm	shm_perm;	/* operation permission struct */
	int		shm_segsz;	/* segment size */
	__VOID__      *	__unused;	/* for binary compatibility */
	unsigned short	shm_lkcnt;
	__pid_t		shm_cpid;	/* pid of creator */
	__pid_t		shm_lpid;	/* pid of last shmop */
	unsigned long	shm_nattch;	/* current # attached */
	unsigned long	shm_cnattach;	/* for binary compatibility */
	__time_t	shm_atime;	/* last shmat time */
	long		__pad1;
	__time_t	shm_dtime;	/* last shmdt time */
	long		__pad2;
	__time_t	shm_ctime;	/* last change time */
	long		__pad3;
	long		__pad4 [4];
};

#else	/* if ! _SYSV4 */

struct shmid_ds {
	struct ipc_perm	shm_perm;	/* operation permission struct */
	int		shm_segsz;	/* segment size */
	__VOID__      *	__unused;	/* for binary compatibility */
	char		__pad [4];	/* for binary compatibility */
	unsigned short	shm_lpid;	/* pid of last shmop */
	unsigned short	shm_cpid;	/* pid of creator */
	unsigned short	shm_nattch;	/* current # attached */
	unsigned short	shm_cnattach;	/* for binary compatibility */
	__time_t	shm_atime;	/* last shmat time */
	__time_t	shm_dtime;	/* last shmdt time */
	__time_t	shm_ctime;	/* last change time */
};

#endif	/* ! _SYSV4 */

#if	_KERNEL

/* Patchable kernel values. */

extern int SHMMAX;	/* Max size in bytes of shared memory segment */
			/* Not more than 4 Megs, please! */

extern int SHMMNI;	/* Maximum # of shared memory segments, systemwide */

#endif

__EXTERN_C_BEGIN__

int		shmctl		__PROTO ((int _shmid, int _cmd,
					  struct shmid_ds * _buf));
int		shmget		__PROTO ((__key_t _key, int _size,
					  int _shmflag));
__VOID__      *	shmat		__PROTO ((int _shmid, __VOID__ * _shmaddr,
					  int _shmflag));
int		shmdt		__PROTO ((__VOID__ * _shmaddr));

__EXTERN_C_END__

#endif /* ! defined (__SYS_SHM_H__) */