glibc/sysdeps/unix/sysv/linux/sys/pidfd.h
Adhemerval Zanella 56cf9e8eec linux: Add pidfd_send_signal
This was added on Linux 5.1(3eb39f47934f9d5a3027fe00d906a45fe3a15fad)
as a way to avoid the race condition of using kill (where PID might be
reused by the kernel between between obtaining the pid and sending the
signal).

If the siginfo_t argument is NULL then pidfd_send_signal is equivalent
to kill.  If it is not NULL pidfd_send_signal is equivalent to
rt_sigqueueinfo.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2022-05-17 10:33:46 -03:00

50 lines
1.8 KiB
C

/* Wrapper for file descriptors that refers to a process functions.
Copyright (C) 2022 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 _PIDFD_H
#include <fcntl.h>
#include <bits/types/siginfo_t.h>
#define PIDFD_NONBLOCK O_NONBLOCK
/* Returns a file descriptor that refers to the process PID. The
close-on-exec is set on the file descriptor.
The FLAGS argument is reserved for future use, it must be specified
as 0. */
extern int pidfd_open (__pid_t __pid, unsigned int __flags) __THROW;
/* Duplicates an existing file descriptor TARGETFD in the process referred
by the PIDFD file descriptor PIDFD.
The FLAGS argument is reserved for future use, it must be specified
as 0. */
extern int pidfd_getfd (int __pidfd, int __targetfd,
unsigned int __flags) __THROW;
/* Sends the signal SIG to the target process referred by the PIDFD. If
INFO points to a siginfo_t buffer, it will be populated.
The FLAGS argument is reserved for future use, it must be specified
as 0. */
extern int pidfd_send_signal (int __pidfd, int __sig, siginfo_t *__info,
unsigned int __flags) __THROW;
#endif /* _PIDFD_H */