/* Checking macros for select functions.

   Copyright (C) 2011-2018 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

   <http://www.gnu.org/licenses/>.  */

#ifndef _SYS_SELECT_H

# error "Never include <bits/select2.h> directly; use <sys/select.h> instead."

#endif

/* Helper functions to issue warnings and errors when needed.  */

extern long int __fdelt_chk (long int __d);

extern long int __fdelt_warn (long int __d)

  __warnattr ("bit outside of fd_set selected");

#undef __FD_ELT

#define	__FD_ELT(d) \

  __extension__								    \

  ({ long int __d = (d);						    \

     (__builtin_constant_p (__d)					    \

      ? (0 <= __d && __d < __FD_SETSIZE					    \

	 ? (__d / __NFDBITS)						    \

	 : __fdelt_warn (__d))						    \

      : __fdelt_chk (__d)); })