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glibc  2.9
shm.h
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00001 /* Copyright (C) 1995,1996,1997,2000,2002,2004,2008
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 
00026 /* Permission flag for shmget.  */
00027 #define SHM_R        0400          /* or S_IRUGO from <linux/stat.h> */
00028 #define SHM_W        0200          /* or S_IWUGO from <linux/stat.h> */
00029 
00030 /* Flags for `shmat'.  */
00031 #define SHM_RDONLY   010000        /* attach read-only else read-write */
00032 #define SHM_RND             020000        /* round attach address to SHMLBA */
00033 #define SHM_REMAP    040000        /* take-over region on attach */
00034 
00035 /* Commands for `shmctl'.  */
00036 #define SHM_LOCK     11            /* lock segment (root only) */
00037 #define SHM_UNLOCK   12            /* unlock segment (root only) */
00038 
00039 __BEGIN_DECLS
00040 
00041 /* Segment low boundary address multiple.  */
00042 #define SHMLBA              (__getpagesize () << 2)
00043 extern int __getpagesize (void) __THROW __attribute__ ((__const__));
00044 
00045 
00046 /* Type to count number of attaches.  */
00047 typedef unsigned long int shmatt_t;
00048 
00049 /* Data structure describing a shared memory segment.  */
00050 struct shmid_ds
00051   {
00052     struct ipc_perm shm_perm;             /* operation permission struct */
00053     size_t shm_segsz;                     /* size of segment in bytes */
00054     __time_t shm_atime;                   /* time of last shmat() */
00055     unsigned long int __unused1;
00056     __time_t shm_dtime;                   /* time of last shmdt() */
00057     unsigned long int __unused2;
00058     __time_t shm_ctime;                   /* time of last change by shmctl() */
00059     unsigned long int __unused3;
00060     __pid_t shm_cpid;                     /* pid of creator */
00061     __pid_t shm_lpid;                     /* pid of last shmop */
00062     shmatt_t shm_nattch;           /* number of current attaches */
00063     unsigned long int __unused4;
00064     unsigned long int __unused5;
00065   };
00066 
00067 #ifdef __USE_MISC
00068 
00069 /* ipcs ctl commands */
00070 # define SHM_STAT    13
00071 # define SHM_INFO    14
00072 
00073 /* shm_mode upper byte flags */
00074 # define SHM_DEST    01000  /* segment will be destroyed on last detach */
00075 # define SHM_LOCKED  02000   /* segment will not be swapped */
00076 # define SHM_HUGETLB 04000  /* segment is mapped via hugetlb */
00077 # define SHM_NORESERVE      010000 /* don't check for reservations */
00078 
00079 struct shminfo
00080   {
00081     unsigned long int shmmax;
00082     unsigned long int shmmin;
00083     unsigned long int shmmni;
00084     unsigned long int shmseg;
00085     unsigned long int shmall;
00086     unsigned long int __unused1;
00087     unsigned long int __unused2;
00088     unsigned long int __unused3;
00089     unsigned long int __unused4;
00090   };
00091 
00092 struct shm_info
00093   {
00094     int used_ids;
00095     unsigned long int shm_tot;     /* total allocated shm */
00096     unsigned long int shm_rss;     /* total resident shm */
00097     unsigned long int shm_swp;     /* total swapped shm */
00098     unsigned long int swap_attempts;
00099     unsigned long int swap_successes;
00100   };
00101 
00102 #endif /* __USE_MISC */
00103 
00104 __END_DECLS