1 /* sysselect.h - System-dependent definitions for the select function.
2 Copyright (C) 1995, 2001-2017 Free Software Foundation, Inc.
4 This file is part of GNU Emacs.
6 GNU Emacs is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or (at
9 your option) any later version.
11 GNU Emacs is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>. */
23 #include <sys/select.h>
28 /* The w32 build defines select stuff in w32.h, which is included
29 where w32 needs it, but not where sysselect.h is included. The w32
30 definitions in w32.h are incompatible with the below. */
40 /* Define the macros to access a single-int bitmap of descriptors. */
41 #define FD_SET(n, p) (*(p) |= (1 << (n)))
42 #define FD_CLR(n, p) (*(p) &= ~(1 << (n)))
43 #define FD_ISSET(n, p) (*(p) & (1 << (n)))
44 #define FD_ZERO(p) (*(p) = 0)
45 #endif /* no FD_SET */
46 #endif /* not WINDOWSNT */
48 #if !defined (HAVE_SELECT)
49 #define select sys_select
53 /* The above #define for 'select' gets in the way because sysselect.h
54 is included in thread.h, which is included everywhere, and 'select'
55 declared in DJGPP system headers has a signature incompatible with
56 'pselect', which we emulate in msdos.c. */
58 #define pselect sys_select
64 /* Check for out-of-range errors if ENABLE_CHECKING is defined. */
67 fd_CLR (int fd
, fd_set
*set
)
69 eassume (0 <= fd
&& fd
< FD_SETSIZE
);
74 fd_ISSET (int fd
, fd_set
*set
)
76 eassume (0 <= fd
&& fd
< FD_SETSIZE
);
77 return FD_ISSET (fd
, set
) != 0;
81 fd_SET (int fd
, fd_set
*set
)
83 eassume (0 <= fd
&& fd
< FD_SETSIZE
);
90 #define FD_CLR(fd, set) fd_CLR (fd, set)
91 #define FD_ISSET(fd, set) fd_ISSET (fd, set)
92 #define FD_SET(fd, set) fd_SET (fd, set)
96 #endif /* !WINDOWSNT */