shmbuf.h

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#ifndef __ASM_GENERIC_SHMBUF_H
#define __ASM_GENERIC_SHMBUF_H

#include <asm/bitsperlong.h>

/*
 * The shmid64_ds structure for x86 architecture.
 * Note extra padding because this structure is passed back and forth
 * between kernel and user space.
 *
 * shmid64_ds was originally meant to be architecture specific, but
 * everyone just ended up making identical copies without specific
 * optimizations, so we may just as well all use the same one.
 *
 * 64 bit architectures typically define a 64 bit __kernel_time_t,
 * so they do not need the first two padding words.
 * On big-endian systems, the padding is in the wrong place.
 *
 *
 * Pad space is left for:
 * - 64-bit time_t to solve y2038 problem
 * - 2 miscellaneous 32-bit values
 */

struct shmid64_ds {
    struct ipc64_perm   shm_perm;   /* operation perms */
    size_t          shm_segsz;  /* size of segment (bytes) */
    __kernel_time_t     shm_atime;  /* last attach time */
#if __BITS_PER_LONG != 64
    unsigned long       __unused1;
#endif
    __kernel_time_t     shm_dtime;  /* last detach time */
#if __BITS_PER_LONG != 64
    unsigned long       __unused2;
#endif
    __kernel_time_t     shm_ctime;  /* last change time */
#if __BITS_PER_LONG != 64
    unsigned long       __unused3;
#endif
    __kernel_pid_t      shm_cpid;   /* pid of creator */
    __kernel_pid_t      shm_lpid;   /* pid of last operator */
    unsigned long       shm_nattch; /* no. of current attaches */
    unsigned long       __unused4;
    unsigned long       __unused5;
};

struct shminfo64 {
    unsigned long   shmmax;
    unsigned long   shmmin;
    unsigned long   shmmni;
    unsigned long   shmseg;
    unsigned long   shmall;
    unsigned long   __unused1;
    unsigned long   __unused2;
    unsigned long   __unused3;
    unsigned long   __unused4;
};

#endif /* __ASM_GENERIC_SHMBUF_H */