select.h (1505B) - Raw
1 /* Copyright (C) 1997-2025 Free Software Foundation, Inc. 2 This file is part of the GNU C Library. 3 4 The GNU C Library is free software; you can redistribute it and/or 5 modify it under the terms of the GNU Lesser General Public 6 License as published by the Free Software Foundation; either 7 version 2.1 of the License, or (at your option) any later version. 8 9 The GNU C Library is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 Lesser General Public License for more details. 13 14 You should have received a copy of the GNU Lesser General Public 15 License along with the GNU C Library; if not, see 16 <https://www.gnu.org/licenses/>. */ 17 18 #ifndef _SYS_SELECT_H 19 # error "Never use <bits/select.h> directly; include <sys/select.h> instead." 20 #endif 21 22 23 /* We don't use `memset' because this would require a prototype and 24 the array isn't too big. */ 25 #define __FD_ZERO(s) \ 26 do { \ 27 unsigned int __i; \ 28 fd_set *__arr = (s); \ 29 for (__i = 0; __i < sizeof (fd_set) / sizeof (__fd_mask); ++__i) \ 30 __FDS_BITS (__arr)[__i] = 0; \ 31 } while (0) 32 #define __FD_SET(d, s) \ 33 ((void) (__FDS_BITS (s)[__FD_ELT(d)] |= __FD_MASK(d))) 34 #define __FD_CLR(d, s) \ 35 ((void) (__FDS_BITS (s)[__FD_ELT(d)] &= ~__FD_MASK(d))) 36 #define __FD_ISSET(d, s) \ 37 ((__FDS_BITS (s)[__FD_ELT (d)] & __FD_MASK (d)) != 0)