Back to index

glibc  2.9
select.h
Go to the documentation of this file.
00001 /* Copyright (C) 1997, 1998, 2001 Free Software Foundation, Inc.
00002    This file is part of the GNU C Library.
00003 
00004    The GNU C Library is free software; you can redistribute it and/or
00005    modify it under the terms of the GNU Lesser General Public
00006    License as published by the Free Software Foundation; either
00007    version 2.1 of the License, or (at your option) any later version.
00008 
00009    The GNU C Library is distributed in the hope that it will be useful,
00010    but WITHOUT ANY WARRANTY; without even the implied warranty of
00011    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00012    Lesser General Public License for more details.
00013 
00014    You should have received a copy of the GNU Lesser General Public
00015    License along with the GNU C Library; if not, write to the Free
00016    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00017    02111-1307 USA.  */
00018 
00019 #ifndef _SYS_SELECT_H
00020 # error "Never use <bits/select.h> directly; include <sys/select.h> instead."
00021 #endif
00022 
00023 
00024 /* We don't use `memset' because this would require a prototype and
00025    the array isn't too big.  */
00026 #define __FD_ZERO(s) \
00027   do {                                                               \
00028     unsigned int __i;                                                       \
00029     fd_set *__arr = (s);                                             \
00030     for (__i = 0; __i < sizeof (fd_set) / sizeof (__fd_mask); ++__i)        \
00031       __FDS_BITS (__arr)[__i] = 0;                                   \
00032   } while (0)
00033 #define __FD_SET(d, s)     (__FDS_BITS (s)[__FDELT(d)] |= __FDMASK(d))
00034 #define __FD_CLR(d, s)     (__FDS_BITS (s)[__FDELT(d)] &= ~__FDMASK(d))
00035 #define __FD_ISSET(d, s)   ((__FDS_BITS (s)[__FDELT(d)] & __FDMASK(d)) != 0)