glibc/sysdeps/unix/sysv/linux/msgrcv.c

49 lines
1.5 KiB
C

/* Copyright (C) 1995-2015 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, August 1995.
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
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <sys/msg.h>
#include <ipc_priv.h>
#include <sysdep-cancel.h>
#include <sys/syscall.h>
/* Kludge to work around Linux' restriction of only up to five
arguments to a system call. */
struct ipc_kludge
{
void *msgp;
long int msgtyp;
};
ssize_t
__libc_msgrcv (int msqid, void *msgp, size_t msgsz, long int msgtyp,
int msgflg)
{
/* The problem here is that Linux' calling convention only allows up to
fives parameters to a system call. */
struct ipc_kludge tmp;
tmp.msgp = msgp;
tmp.msgtyp = msgtyp;
return SYSCALL_CANCEL (ipc, IPCOP_msgrcv, msqid, msgsz, msgflg, &tmp);
}
weak_alias (__libc_msgrcv, msgrcv)