/* System-specific extensions of <unistd.h>, Linux version.
Copyright (C) 2019-2021 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
<https://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;
#ifdef __has_include
# if __has_include ("linux/close_range.h")
# include "linux/close_range.h"
# endif
#endif
/* Unshare the file descriptor table before closing file descriptors. */
#ifndef CLOSE_RANGE_UNSHARE
# define CLOSE_RANGE_UNSHARE (1U << 1)
#endif
/* Set the FD_CLOEXEC bit instead of closing the file descriptor. */
#ifndef CLOSE_RANGE_CLOEXEC
# define CLOSE_RANGE_CLOEXEC (1U << 2)
#endif
/* Close all file descriptors in the range FD up to MAX_FD. The flag FLAGS
are define by the CLOSE_RANGE prefix. This function behaves like close
on the range, but in a fail-safe where it will either fail and not close
any file descriptor or close all of them. Gaps where the file descriptor
is invalid are ignored. Returns 0 on successor or -1 for failure (and
sets errno accordingly). */
extern int close_range (unsigned int __fd, unsigned int __max_fd,
int __flags) __THROW;
#endif /* __USE_GNU */
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