sysvipc/sys/msg.h

   1 /* Copyright (C) 1995,1996,1997,1999,2000,2003 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #ifndef _SYS_MSG_H
  20 #define _SYS_MSG_H
  21
  22 #include <features.h>
  23
  24 /* Get common definition of System V style IPC.  */
  25 #include <sys/ipc.h>
  26
  27 /* Get system dependent definition of `struct msqid_ds' and more.  */
  28 #include <bits/msq.h>
  29
  30 /* Define types required by the standard.  */
  31 #define __need_time_t
  32 #include <time.h>
  33
  34 #ifndef __pid_t_defined
  35 typedef __pid_t pid_t;
  36 # define __pid_t_defined
  37 #endif
  38
  39 #ifndef __ssize_t_defined
  40 typedef __ssize_t ssize_t;
  41 # define __ssize_t_defined
  42 #endif
  43
  44 /* The following System V style IPC functions implement a message queue
  45    system.  The definition is found in XPG2.  */
  46
  47 #ifdef __USE_GNU
  48 /* Template for struct to be used as argument for `msgsnd' and `msgrcv'.  */
  49 struct msgbuf
  50   {
  51     long int mtype;             /* type of received/sent message */
  52     char mtext[1];              /* text of the message */
  53   };
  54 #endif
  55
  56
  57 __BEGIN_DECLS
  58
  59 /* Message queue control operation.  */
  60 extern int msgctl (int __msqid, int __cmd, struct msqid_ds *__buf) __THROW;
  61
  62 /* Get messages queue.  */
  63 extern int msgget (key_t __key, int __msgflg) __THROW;
  64
  65 /* Receive message from message queue.
  66
  67    This function is a cancellation point and therefore not marked with
  68    __THROW.  */
  69 extern int msgrcv (int __msqid, void *__msgp, size_t __msgsz,
  70                    long int __msgtyp, int __msgflg);
  71
  72 /* Send message to message queue.
  73
  74    This function is a cancellation point and therefore not marked with
  75    __THROW.  */
  76 extern int msgsnd (int __msqid, __const void *__msgp, size_t __msgsz,
  77                    int __msgflg);
  78
  79 __END_DECLS
  80
  81 #endif /* sys/msg.h */