1 | /* System-specific extensions of <unistd.h>, Linux version. |
2 | Copyright (C) 2019-2022 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 _UNISTD_H |
20 | # error "Never include <bits/unistd_ext.h> directly; use <unistd.h> instead." |
21 | #endif |
22 | |
23 | #ifdef __USE_GNU |
24 | |
25 | /* Return the kernel thread ID (TID) of the current thread. The |
26 | returned value is not subject to caching. Most Linux system calls |
27 | accept a TID in place of a PID. Using the TID to change properties |
28 | of a thread that has been created using pthread_create can lead to |
29 | undefined behavior (comparable to manipulating file descriptors |
30 | directly that have not been created explicitly). Note that a TID |
31 | uniquely identifies a thread only while this thread is running; a |
32 | TID can be reused once a thread has exited, even if the thread is |
33 | not detached and has not been joined. */ |
34 | extern __pid_t gettid (void) __THROW; |
35 | |
36 | #ifdef __has_include |
37 | # if __has_include ("linux/close_range.h") |
38 | # include "linux/close_range.h" |
39 | # endif |
40 | #endif |
41 | /* Unshare the file descriptor table before closing file descriptors. */ |
42 | #ifndef CLOSE_RANGE_UNSHARE |
43 | # define CLOSE_RANGE_UNSHARE (1U << 1) |
44 | #endif |
45 | /* Set the FD_CLOEXEC bit instead of closing the file descriptor. */ |
46 | #ifndef CLOSE_RANGE_CLOEXEC |
47 | # define CLOSE_RANGE_CLOEXEC (1U << 2) |
48 | #endif |
49 | |
50 | #endif /* __USE_GNU */ |
51 | |