The C and C++ Include Header Files

/usr/include/x86_64-linux-gnu/sys/poll.h


$ cat -n /usr/include/x86_64-linux-gnu/sys/poll.h

     1	/* Compatibility definitions for System V `poll' interface.
     2	   Copyright (C) 1994-2024 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 */