1 /* Copyright (C) 1995-1997,1999,2000,2003,2006,2007,2012
2    Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <http://www.gnu.org/licenses/>.  */
18 
19 #ifndef _SYS_MSG_H
20 #define _SYS_MSG_H
21 
22 #include <features.h>
23 
24 #define __need_size_t
25 #include <stddef.h>
26 
27 /* Get common definition of System V style IPC.  */
28 #include <sys/ipc.h>
29 
30 /* Get system dependent definition of `struct msqid_ds' and more.  */
31 #include <bits/msq.h>
32 
33 /* Define types required by the standard.  */
34 #define	__need_time_t
35 #include <time.h>
36 
37 #ifndef __pid_t_defined
38 typedef __pid_t pid_t;
39 # define __pid_t_defined
40 #endif
41 
42 #ifndef __ssize_t_defined
43 typedef __ssize_t ssize_t;
44 # define __ssize_t_defined
45 #endif
46 
47 /* The following System V style IPC functions implement a message queue
48    system.  The definition is found in XPG2.  */
49 
50 #ifdef __USE_GNU
51 /* Template for struct to be used as argument for `msgsnd' and `msgrcv'.  */
52 struct msgbuf
53   {
54     __syscall_slong_t mtype;	/* type of received/sent message */
55     char mtext[1];		/* text of the message */
56   };
57 #endif
58 
59 
60 __BEGIN_DECLS
61 
62 /* Message queue control operation.  */
63 extern int msgctl (int __msqid, int __cmd, struct msqid_ds *__buf) __THROW;
64 
65 /* Get messages queue.  */
66 extern int msgget (key_t __key, int __msgflg) __THROW;
67 
68 /* Receive message from message queue.
69 
70    This function is a cancellation point and therefore not marked with
71    __THROW.  */
72 extern ssize_t msgrcv (int __msqid, void *__msgp, size_t __msgsz,
73 		       long int __msgtyp, int __msgflg);
74 
75 /* Send message to message queue.
76 
77    This function is a cancellation point and therefore not marked with
78    __THROW.  */
79 extern int msgsnd (int __msqid, const void *__msgp, size_t __msgsz,
80 		   int __msgflg);
81 
82 __END_DECLS
83 
84 #endif /* sys/msg.h */
85