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glibc  2.9
shm.h
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00001 /* Copyright (C) 1995,1996,1997,2000,2002,2004 Free Software Foundation, Inc.
00002    This file is part of the GNU C Library.
00003 
00004    The GNU C Library is free software; you can redistribute it and/or
00005    modify it under the terms of the GNU Lesser General Public
00006    License as published by the Free Software Foundation; either
00007    version 2.1 of the License, or (at your option) any later version.
00008 
00009    The GNU C Library is distributed in the hope that it will be useful,
00010    but WITHOUT ANY WARRANTY; without even the implied warranty of
00011    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00012    Lesser General Public License for more details.
00013 
00014    You should have received a copy of the GNU Lesser General Public
00015    License along with the GNU C Library; if not, write to the Free
00016    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00017    02111-1307 USA.  */
00018 
00019 #ifndef _SYS_SHM_H
00020 # error "Never include <bits/shm.h> directly; use <sys/shm.h> instead."
00021 #endif
00022 
00023 #include <bits/types.h>
00024 
00025 /* Permission flag for shmget.  */
00026 #define SHM_R        0400          /* or S_IRUGO from <linux/stat.h> */
00027 #define SHM_W        0200          /* or S_IWUGO from <linux/stat.h> */
00028 
00029 /* Flags for `shmat'.  */
00030 #define SHM_RDONLY   010000        /* attach read-only else read-write */
00031 #define SHM_RND             020000        /* round attach address to SHMLBA */
00032 #define SHM_REMAP    040000        /* take-over region on attach */
00033 
00034 /* Commands for `shmctl'.  */
00035 #define SHM_LOCK     11            /* lock segment (root only) */
00036 #define SHM_UNLOCK   12            /* unlock segment (root only) */
00037 
00038 __BEGIN_DECLS
00039 
00040 /* Segment low boundary address multiple.  */
00041 #define SHMLBA              (__getpagesize ())
00042 extern int __getpagesize (void) __THROW __attribute__ ((__const__));
00043 
00044 
00045 /* Type to count number of attaches.  */
00046 typedef unsigned long int shmatt_t;
00047 
00048 /* Data structure describing a shared memory segment.  */
00049 struct shmid_ds
00050   {
00051     struct ipc_perm shm_perm;             /* operation permission struct */
00052     size_t shm_segsz;                     /* size of segment in bytes */
00053     __time_t shm_atime;                   /* time of last shmat() */
00054     unsigned long int __unused1;
00055     __time_t shm_dtime;                   /* time of last shmdt() */
00056     unsigned long int __unused2;
00057     __time_t shm_ctime;                   /* time of last change by shmctl() */
00058     unsigned long int __unused3;
00059     __pid_t shm_cpid;                     /* pid of creator */
00060     __pid_t shm_lpid;                     /* pid of last shmop */
00061     shmatt_t shm_nattch;           /* number of current attaches */
00062     unsigned long int __unused4;
00063     unsigned long int __unused5;
00064   };
00065 
00066 #ifdef __USE_MISC
00067 
00068 /* ipcs ctl commands */
00069 # define SHM_STAT    13
00070 # define SHM_INFO    14
00071 
00072 /* shm_mode upper byte flags */
00073 # define SHM_DEST    01000  /* segment will be destroyed on last detach */
00074 # define SHM_LOCKED  02000   /* segment will not be swapped */
00075 # define SHM_HUGETLB 04000  /* segment is mapped via hugetlb */
00076 # define SHM_NORESERVE      010000 /* don't check for reservations */
00077 
00078 struct shminfo
00079   {
00080     unsigned long int shmmax;
00081     unsigned long int shmmin;
00082     unsigned long int shmmni;
00083     unsigned long int shmseg;
00084     unsigned long int shmall;
00085     unsigned long int __unused1;
00086     unsigned long int __unused2;
00087     unsigned long int __unused3;
00088     unsigned long int __unused4;
00089   };
00090 
00091 struct shm_info
00092   {
00093     int used_ids;
00094     unsigned long int shm_tot;     /* total allocated shm */
00095     unsigned long int shm_rss;     /* total resident shm */
00096     unsigned long int shm_swp;     /* total swapped shm */
00097     unsigned long int swap_attempts;
00098     unsigned long int swap_successes;
00099   };
00100 
00101 #endif /* __USE_MISC */
00102 
00103 __END_DECLS