1 /* Copyright (C) 1995-2022 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, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #ifndef _SYS_MSG_H
19 # error "Never use <bits/msq.h> directly; include <sys/msg.h> instead."
20 #endif
21 
22 #include <bits/types.h>
23 #include <bits/ipctypes.h>
24 
25 /* Define options for message queue functions.  */
26 #define MSG_NOERROR	010000	/* no error if message is too big */
27 #ifdef __USE_GNU
28 # define MSG_EXCEPT	020000	/* recv any msg except of specified type */
29 #endif
30 
31 /* Types used in the structure definition.  */
32 typedef unsigned short int msgqnum_t;
33 typedef unsigned short int msglen_t;
34 
35 
36 /* Structure of record for one message inside the kernel.
37    The type `struct msg' is opaque.  */
38 struct msqid_ds
39 {
40   struct ipc_perm msg_perm;	/* structure describing operation permission */
41   struct msg *__msg_first;	/* pointer to first message on queue */
42   struct msg *__msg_last;	/* pointer to last message on queue */
43   __time_t msg_stime;		/* time of last msgsnd command */
44   __time_t msg_rtime;		/* time of last msgrcv command */
45   __time_t msg_ctime;		/* time of last change */
46   struct __wait_queue *__wwait;	/* ??? */
47   struct __wait_queue *__rwait;	/* ??? */
48   unsigned short int __msg_cbytes;/* current number of bytes on queue */
49   msgqnum_t msg_qnum;		/* number of messages currently on queue */
50   msglen_t msg_qbytes;		/* max number of bytes allowed on queue */
51   __ipc_pid_t msg_lspid;	/* pid of last msgsnd() */
52   __ipc_pid_t msg_lrpid;	/* pid of last msgrcv() */
53 };
54 
55 #ifdef __USE_MISC
56 
57 # define msg_cbytes	__msg_cbytes
58 
59 /* ipcs ctl commands */
60 # define MSG_STAT 11
61 # define MSG_INFO 12
62 
63 /* buffer for msgctl calls IPC_INFO, MSG_INFO */
64 struct msginfo
65   {
66     int msgpool;
67     int msgmap;
68     int msgmax;
69     int msgmnb;
70     int msgmni;
71     int msgssz;
72     int msgtql;
73     unsigned short int msgseg;
74   };
75 
76 #endif /* __USE_MISC */
77