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glibc  2.9
shm.h
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00001 /* Copyright (C) 1995, 1996, 1997, 2000, 2002, 2004
00002    Free Software Foundation, Inc.
00003    This file is part of the GNU C Library.
00004 
00005    The GNU C Library is free software; you can redistribute it and/or
00006    modify it under the terms of the GNU Lesser General Public
00007    License as published by the Free Software Foundation; either
00008    version 2.1 of the License, or (at your option) any later version.
00009 
00010    The GNU C Library is distributed in the hope that it will be useful,
00011    but WITHOUT ANY WARRANTY; without even the implied warranty of
00012    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00013    Lesser General Public License for more details.
00014 
00015    You should have received a copy of the GNU Lesser General Public
00016    License along with the GNU C Library; if not, write to the Free
00017    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00018    02111-1307 USA.  */
00019 
00020 #ifndef _SYS_SHM_H
00021 # error "Never include <bits/shm.h> directly; use <sys/shm.h> instead."
00022 #endif
00023 
00024 #include <bits/types.h>
00025 #include <bits/wordsize.h>
00026 
00027 /* Permission flag for shmget.  */
00028 #define SHM_R        0400          /* or S_IRUGO from <linux/stat.h> */
00029 #define SHM_W        0200          /* or S_IWUGO from <linux/stat.h> */
00030 
00031 /* Flags for `shmat'.  */
00032 #define SHM_RDONLY   010000        /* attach read-only else read-write */
00033 #define SHM_RND             020000        /* round attach address to SHMLBA */
00034 #define SHM_REMAP    040000        /* take-over region on attach */
00035 
00036 /* Commands for `shmctl'.  */
00037 #define SHM_LOCK     11            /* lock segment (root only) */
00038 #define SHM_UNLOCK   12            /* unlock segment (root only) */
00039 
00040 __BEGIN_DECLS
00041 
00042 /* Segment low boundary address multiple.  */
00043 #define SHMLBA              (__getpagesize ())
00044 extern int __getpagesize (void) __THROW __attribute__ ((__const__));
00045 
00046 
00047 /* Type to count number of attaches.  */
00048 typedef unsigned long int shmatt_t;
00049 
00050 /* Data structure describing a shared memory segment.  */
00051 struct shmid_ds
00052   {
00053     struct ipc_perm shm_perm;             /* operation permission struct */
00054 #if __WORDSIZE == 32
00055     unsigned int __pad1;
00056 #endif
00057     __time_t shm_atime;                   /* time of last shmat() */
00058 #if __WORDSIZE == 32
00059     unsigned int __pad2;
00060 #endif
00061     __time_t shm_dtime;                   /* time of last shmdt() */
00062 #if __WORDSIZE == 32
00063     unsigned int __pad3;
00064 #endif
00065     __time_t shm_ctime;                   /* time of last change by shmctl() */
00066     size_t shm_segsz;                     /* size of segment in bytes */
00067     __pid_t shm_cpid;                     /* pid of creator */
00068     __pid_t shm_lpid;                     /* pid of last shmop */
00069     shmatt_t shm_nattch;           /* number of current attaches */
00070     unsigned long int __unused1;
00071     unsigned long int __unused2;
00072   };
00073 
00074 #ifdef __USE_MISC
00075 
00076 /* ipcs ctl commands */
00077 # define SHM_STAT    13
00078 # define SHM_INFO    14
00079 
00080 /* shm_mode upper byte flags */
00081 # define SHM_DEST    01000  /* segment will be destroyed on last detach */
00082 # define SHM_LOCKED  02000   /* segment will not be swapped */
00083 # define SHM_HUGETLB 04000  /* segment is mapped via hugetlb */
00084 # define SHM_NORESERVE      010000 /* don't check for reservations */
00085 
00086 struct shminfo
00087   {
00088     unsigned long shmmax;
00089     unsigned long shmmin;
00090     unsigned long shmmni;
00091     unsigned long shmseg;
00092     unsigned long shmall;
00093     unsigned long __unused1;
00094     unsigned long __unused2;
00095     unsigned long __unused3;
00096     unsigned long __unused4;
00097   };
00098 
00099 struct shm_info
00100   {
00101     int used_ids;
00102     unsigned long int shm_tot;     /* total allocated shm */
00103     unsigned long int shm_rss;     /* total resident shm */
00104     unsigned long int shm_swp;     /* total swapped shm */
00105     unsigned long int swap_attempts;
00106     unsigned long int swap_successes;
00107   };
00108 
00109 #endif /* __USE_MISC */
00110 
00111 __END_DECLS