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Diffstat (limited to 'io/sys/poll.h')
| -rw-r--r-- | io/sys/poll.h | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/io/sys/poll.h b/io/sys/poll.h new file mode 100644 index 0000000000..48b9afac9e --- /dev/null +++ b/io/sys/poll.h @@ -0,0 +1,65 @@ +/* Compatibility definitions for System V `poll' interface. +Copyright (C) 1994 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., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#ifndef _SYS_POLL_H +#define _SYS_POLL_H + +#include <sys/cdefs.h> + +/* Data structure describing a polling request. */ +struct pollfd + { + int fd; /* File descriptor to poll. */ + short int events; /* Types of events poller cares about. */ + short int revents; /* Types of events that actually occurred. */ + }; + +/* 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 01 /* There is data to read. */ +#define POLLPRI 02 /* There is urgent data to read. */ +#define POLLOUT 04 /* Writing now will not block. */ + +/* 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 010 /* Error condition. */ +#define POLLHUP 020 /* Hung up. */ +#define POLLNVAL 040 /* Invalid polling request. */ + +/* Canonical number of polling requests to read in at a time in poll. */ +#define NPOLLFILE 30 + + +__BEGIN_DECLS + +/* Poll the file descriptors described by the NFDS structures starting at + FDS. If TIMEOUT is nonzero and not -1, allow TIMEOUT milliseconds for + an event to occur; if TIMEOUT is -1, block until an event occurs. + Returns the number of file descriptors with events, zero if timed out, + or -1 for errors. */ + +extern int poll __P ((struct pollfd *__fds, unsigned long int __nfds, + int __timeout)); + +__END_DECLS + +#endif /* sys/poll.h */ + |