/* Copyright (C) 1997-2021 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
. */
#ifndef _SYS_POLL_H
# error "Never use directly; include instead."
#endif
/* Event types that can be polled for. These bits may be set in `events'
to indicate the interesting event types; they will appear in `revents'
to indicate the status of the file descriptor. */
#define POLLIN 0x001 /* There is data to read. */
#define POLLPRI 0x002 /* There is urgent data to read. */
#define POLLOUT 0x004 /* Writing now will not block. */
#if defined __USE_XOPEN || defined __USE_XOPEN2K8
/* These values are defined in XPG4.2. */
# define POLLRDNORM 0x040 /* Normal data may be read. */
# define POLLRDBAND 0x080 /* Priority data may be read. */
# define POLLWRNORM POLLOUT /* Writing now will not block. */
# define POLLWRBAND 0x100 /* Priority data may be written. */
#endif
#ifdef __USE_GNU
/* These are extensions for Linux. */
# define POLLMSG 0x200
# define POLLREMOVE 0x400
# define POLLRDHUP 0x800
#endif
/* Event types always implicitly polled for. These bits need not be set in
`events', but they will appear in `revents' to indicate the status of
the file descriptor. */
#define POLLERR 0x008 /* Error condition. */
#define POLLHUP 0x010 /* Hung up. */
#define POLLNVAL 0x020 /* Invalid polling request. */