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

63 lines
1.9 KiB
C

/* Poll system call, with emulation if it is not available.
Copyright (C) 1997, 1998 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <errno.h>
#include <sys/poll.h>
#include <sysdep.h>
#include <sys/syscall.h>
#ifdef __NR_poll
extern int __syscall_poll __P ((struct pollfd *fds, unsigned int nfds,
int timeout));
static int __emulate_poll __P ((struct pollfd *fds, unsigned long int nfds,
int timeout)) internal_function;
/* The real implementation. */
int
__poll (fds, nfds, timeout)
struct pollfd *fds;
unsigned long int nfds;
int timeout;
{
static int must_emulate = 0;
if (!must_emulate)
{
int errno_saved = errno;
int retval = INLINE_SYSCALL (poll, 3, fds, nfds, timeout);
if (retval >= 0 || errno != ENOSYS)
return retval;
__set_errno (errno_saved);
must_emulate = 1;
}
return __emulate_poll (fds, nfds, timeout);
}
weak_alias (__poll, poll)
/* Get the emulation code. */
# define __poll(fds, nfds, timeout) \
static internal_function __emulate_poll (fds, nfds, timeout)
#endif
#include <sysdeps/unix/bsd/poll.c>