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glibc  2.9
shm.h
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00001 /* Copyright (C) 2001, 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 #include <bits/wordsize.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 ())
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 #if __WORDSIZE != 64
00056   unsigned long int __unused1;
00057 #endif
00058     __time_t shm_dtime;                   /* time of last shmdt() */
00059 #if __WORDSIZE != 64
00060   unsigned long int __unused2;
00061 #endif
00062     __time_t shm_ctime;                   /* time of last change by shmctl() */
00063 #if __WORDSIZE != 64
00064   unsigned long int __unused3;
00065 #endif
00066     __pid_t shm_cpid;                     /* pid of creator */
00067     __pid_t shm_lpid;                     /* pid of last shmop */
00068     shmatt_t shm_nattch;           /* number of current attaches */
00069     unsigned long int __unused4;
00070     unsigned long int __unused5;
00071   };
00072 
00073 #ifdef __USE_MISC
00074 
00075 /* ipcs ctl commands */
00076 # define SHM_STAT    13
00077 # define SHM_INFO    14
00078 
00079 /* shm_mode upper byte flags */
00080 # define SHM_DEST    01000  /* segment will be destroyed on last detach */
00081 # define SHM_LOCKED  02000  /* segment will not be swapped */
00082 # define SHM_HUGETLB 04000  /* segment is mapped via hugetlb */
00083 # define SHM_NORESERVE      010000 /* don't check for reservations */
00084 
00085 struct shminfo
00086   {
00087     unsigned long int shmmax;
00088     unsigned long int shmmin;
00089     unsigned long int shmmni;
00090     unsigned long int shmseg;
00091     unsigned long int shmall;
00092     unsigned long int __unused1;
00093     unsigned long int __unused2;
00094     unsigned long int __unused3;
00095     unsigned long int __unused4;
00096   };
00097 
00098 struct shm_info
00099   {
00100     int used_ids;
00101     unsigned long int shm_tot;     /* total allocated shm */
00102     unsigned long int shm_rss;     /* total resident shm */
00103     unsigned long int shm_swp;     /* total swapped shm */
00104     unsigned long int swap_attempts;
00105     unsigned long int swap_successes;
00106   };
00107 
00108 #endif /* __USE_MISC */
00109 
00110 __END_DECLS