| /* System-specific extensions of <unistd.h>, Linux version. |
| Copyright (C) 2019 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 _UNISTD_H |
| # error "Never include <bits/unistd_ext.h> directly; use <unistd.h> instead." |
| #endif |
| |
| #ifdef __USE_GNU |
| |
| /* Return the kernel thread ID (TID) of the current thread. The |
| returned value is not subject to caching. Most Linux system calls |
| accept a TID in place of a PID. Using the TID to change properties |
| of a thread that has been created using pthread_create can lead to |
| undefined behavior (comparable to manipulating file descriptors |
| directly that have not been created explicitly). Note that a TID |
| uniquely identifies a thread only while this thread is running; a |
| TID can be reused once a thread has exited, even if the thread is |
| not detached and has not been joined. */ |
| extern __pid_t gettid (void) __THROW; |
| |
| #endif |
