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glibc  2.9
shm.h
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00001 /* Copyright (C) 1995, 1996, 1997, 2000, 2002 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 /* Segment low boundary address multiple.  */
00040 #define SHMLBA 0x00400000          /* address needs to be 4 Mb aligned */
00041 
00042 /* Type to count number of attaches.  */
00043 typedef unsigned long int shmatt_t;
00044 
00045 /* Data structure describing a shared memory segment.  */
00046 struct shmid_ds
00047   {
00048     struct ipc_perm shm_perm;             /* operation permission struct */
00049 #if __WORDSIZE == 32
00050     unsigned int __pad1;
00051 #endif
00052     __time_t shm_atime;                   /* time of last shmat() */
00053 #if __WORDSIZE == 32
00054     unsigned int __pad2;
00055 #endif
00056     __time_t shm_dtime;                   /* time of last shmdt() */
00057 #if __WORDSIZE == 32
00058     unsigned int __pad3;
00059 #endif
00060     __time_t shm_ctime;                   /* time of last change by shmctl() */
00061 #if __WORDSIZE == 32
00062     unsigned int __pad4;
00063 #endif
00064     size_t shm_segsz;                     /* size of segment in bytes */
00065     __pid_t shm_cpid;                     /* pid of creator */
00066     __pid_t shm_lpid;                     /* pid of last shmop */
00067     shmatt_t shm_nattch;           /* number of current attaches */
00068     unsigned long int __unused1;
00069     unsigned long int __unused2;
00070   };
00071 
00072 #ifdef __USE_MISC
00073 
00074 /* ipcs ctl commands */
00075 # define SHM_STAT    13
00076 # define SHM_INFO    14
00077 
00078 /* shm_mode upper byte flags */
00079 # define SHM_DEST    01000  /* segment will be destroyed on last detach */
00080 # define SHM_LOCKED  02000   /* segment will not be swapped */
00081 # define SHM_HUGETLB 04000  /* segment is mapped via hugetlb */
00082 # define SHM_NORESERVE      010000 /* don't check for reservations */
00083 
00084 struct shminfo
00085   {
00086     unsigned long shmmax;
00087     unsigned long shmmin;
00088     unsigned long shmmni;
00089     unsigned long shmseg;
00090     unsigned long shmall;
00091     unsigned long __unused1;
00092     unsigned long __unused2;
00093     unsigned long __unused3;
00094     unsigned long __unused4;
00095   };
00096 
00097 struct shm_info
00098   {
00099     int used_ids;
00100     unsigned long int shm_tot;     /* total allocated shm */
00101     unsigned long int shm_rss;     /* total resident shm */
00102     unsigned long int shm_swp;     /* total swapped shm */
00103     unsigned long int swap_attempts;
00104     unsigned long int swap_successes;
00105   };
00106 
00107 #endif /* __USE_MISC */