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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 
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 #if __WORDSIZE == 32
00054     unsigned int __unused1;
00055 #endif
00056     __time_t shm_atime;                        /* time of last shmat() */
00057 #if __WORDSIZE == 32
00058     unsigned int __unused2;
00059 #endif
00060     __time_t shm_dtime;                        /* time of last shmdt() */
00061 #if __WORDSIZE == 32
00062     unsigned int __unused3;
00063 #endif
00064     __time_t shm_ctime;                   /* time of last change by shmctl() */
00065 #if __WORDSIZE == 32
00066     unsigned int __unused4;
00067 #endif
00068     size_t shm_segsz;                  /* size of segment in bytes */
00069     __pid_t shm_cpid;                  /* pid of creator */
00070     __pid_t shm_lpid;                  /* pid of last shmop */
00071     shmatt_t shm_nattch;               /* number of current attaches */
00072     unsigned long __unused5;
00073     unsigned long __unused6;
00074   };
00075 
00076 #ifdef __USE_MISC
00077 
00078 /* ipcs ctl commands */
00079 # define SHM_STAT      13
00080 # define SHM_INFO      14
00081 
00082 /* shm_mode upper byte flags */
00083 # define SHM_DEST      01000       /* segment will be destroyed on last detach */
00084 # define SHM_LOCKED    02000       /* segment will not be swapped */
00085 # define SHM_HUGETLB   04000       /* segment is mapped via hugetlb */
00086 # define SHM_NORESERVE 010000      /* don't check for reservations */
00087 
00088 struct shminfo
00089   {
00090     unsigned long int shmmax;
00091     unsigned long int shmmin;
00092     unsigned long int shmmni;
00093     unsigned long int shmseg;
00094     unsigned long int shmall;
00095     unsigned long int __unused1;
00096     unsigned long int __unused2;
00097     unsigned long int __unused3;
00098     unsigned long int __unused4;
00099   };
00100 
00101 struct shm_info
00102   {
00103     int used_ids;
00104     unsigned long int shm_tot; /* total allocated shm */
00105     unsigned long int shm_rss; /* total resident shm */
00106     unsigned long int shm_swp; /* total swapped shm */
00107     unsigned long int swap_attempts;
00108     unsigned long int swap_successes;
00109   };
00110 
00111 #endif /* __USE_MISC */
00112 
00113 __END_DECLS