/* Copyright (C) 1995-2020 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ #ifndef _SYS_MSG_H #define _SYS_MSG_H #include <features.h> #define __need_size_t #include <stddef.h> /* Get common definition of System V style IPC. */ #include <sys/ipc.h> /* Get system dependent definition of `struct msqid_ds' and more. */ #include <bits/msq.h> /* Define types required by the standard. */ #include <bits/types/time_t.h> #ifndef __pid_t_defined typedef __pid_t pid_t; # define __pid_t_defined #endif #ifndef __ssize_t_defined typedef __ssize_t ssize_t; # define __ssize_t_defined #endif /* The following System V style IPC functions implement a message queue system. The definition is found in XPG2. */ #ifdef __USE_GNU /* Template for struct to be used as argument for `msgsnd' and `msgrcv'. */ struct msgbuf { __syscall_slong_t mtype; /* type of received/sent message */ char mtext[1]; /* text of the message */ }; #endif __BEGIN_DECLS /* Message queue control operation. */ extern int msgctl (int __msqid, int __cmd, struct msqid_ds *__buf) __THROW; /* Get messages queue. */ extern int msgget (key_t __key, int __msgflg) __THROW; /* Receive message from message queue. This function is a cancellation point and therefore not marked with __THROW. */ extern ssize_t msgrcv (int __msqid, void *__msgp, size_t __msgsz, long int __msgtyp, int __msgflg); /* Send message to message queue. This function is a cancellation point and therefore not marked with __THROW. */ extern int msgsnd (int __msqid, const void *__msgp, size_t __msgsz, int __msgflg); __END_DECLS #endif /* sys/msg.h */