1  /* Compatibility definitions for System V `poll' interface.
       2     Copyright (C) 1994-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #ifndef	_SYS_POLL_H
      20  #define	_SYS_POLL_H	1
      21  
      22  #include <features.h>
      23  
      24  /* Get the platform dependent bits of `poll'.  */
      25  #include <bits/poll.h>
      26  #ifdef __USE_GNU
      27  # include <bits/types/__sigset_t.h>
      28  # include <bits/types/struct_timespec.h>
      29  #endif
      30  
      31  
      32  /* Type used for the number of file descriptors.  */
      33  typedef unsigned long int nfds_t;
      34  
      35  /* Data structure describing a polling request.  */
      36  struct pollfd
      37    {
      38      int fd;			/* File descriptor to poll.  */
      39      short int events;		/* Types of events poller cares about.  */
      40      short int revents;		/* Types of events that actually occurred.  */
      41    };
      42  
      43  
      44  __BEGIN_DECLS
      45  
      46  /* Poll the file descriptors described by the NFDS structures starting at
      47     FDS.  If TIMEOUT is nonzero and not -1, allow TIMEOUT milliseconds for
      48     an event to occur; if TIMEOUT is -1, block until an event occurs.
      49     Returns the number of file descriptors with events, zero if timed out,
      50     or -1 for errors.
      51  
      52     This function is a cancellation point and therefore not marked with
      53     __THROW.  */
      54  extern int poll (struct pollfd *__fds, nfds_t __nfds, int __timeout)
      55      __fortified_attr_access (__write_only__, 1, 2);
      56  
      57  #ifdef __USE_GNU
      58  /* Like poll, but before waiting the threads signal mask is replaced
      59     with that specified in the fourth parameter.  For better usability,
      60     the timeout value is specified using a TIMESPEC object.
      61  
      62     This function is a cancellation point and therefore not marked with
      63     __THROW.  */
      64  extern int ppoll (struct pollfd *__fds, nfds_t __nfds,
      65  		  const struct timespec *__timeout,
      66  		  const __sigset_t *__ss)
      67      __fortified_attr_access (__write_only__, 1, 2);
      68  
      69  # ifdef __USE_TIME_BITS64
      70  #  ifdef __REDIRECT
      71  extern int __REDIRECT (ppoll, (struct pollfd *__fds, nfds_t __nfds,
      72                                 const struct timespec *__timeout,
      73                                 const __sigset_t *__ss),
      74                         __ppoll64)
      75      __fortified_attr_access (__write_only__, 1, 2);
      76  #  else
      77  #  define ppoll __ppoll64
      78  #  endif
      79  # endif
      80  #endif
      81  
      82  __END_DECLS
      83  
      84  
      85  /* Define some inlines helping to catch common problems.  */
      86  #if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
      87  # include <bits/poll2.h>
      88  #endif
      89  
      90  #endif	/* sys/poll.h */