отправить сигнал в поток (send a signal to a thread)
Имя (Name)
tkill, tgkill - send a signal to a thread
Синопсис (Synopsis)
#include <signal.h> /* Definition of SIG* constants */
#include <sys/syscall.h> /* Definition of SYS_* constants */
#include <unistd.h>
int syscall(SYS_tkill, pid_t tid, int sig);
#include <signal.h>
int tgkill(pid_t tgid, pid_t tid, int sig);
Note: glibc provides no wrapper for tkill(), necessitating the
use of syscall(2).
Описание (Description)
tgkill() sends the signal sig to the thread with the thread ID
tid in the thread group tgid. (By contrast, kill(2) can be used
to send a signal only to a process (i.e., thread group) as a
whole, and the signal will be delivered to an arbitrary thread
within that process.)
tkill() is an obsolete predecessor to tgkill(). It allows only
the target thread ID to be specified, which may result in the
wrong thread being signaled if a thread terminates and its thread
ID is recycled. Avoid using this system call.
These are the raw system call interfaces, meant for internal
thread library use.
Возвращаемое значение (Return value)
On success, zero is returned. On error, -1 is returned, and
errno is set to indicate the error.
Ошибки (Error)
EAGAIN The RLIMIT_SIGPENDING resource limit was reached and sig
is a real-time signal.
EAGAIN Insufficient kernel memory was available and sig is a
real-time signal.
EINVAL An invalid thread ID, thread group ID, or signal was
specified.
EPERM Permission denied. For the required permissions, see
kill(2).
ESRCH No process with the specified thread ID (and thread group
ID) exists.
Версии (Versions)
tkill() is supported since Linux 2.4.19 / 2.5.4. tgkill() was
added in Linux 2.5.75.
Library support for tgkill() was added to glibc in version 2.30.
Стандарты (Conforming to)
tkill() and tgkill() are Linux-specific and should not be used in
programs that are intended to be portable.
Примечание (Note)
See the description of CLONE_THREAD in clone(2) for an
explanation of thread groups.
Before glibc 2.30, there was also no wrapper function for
tgkill().
Смотри также (See also)
clone(2), gettid(2), kill(2), rt_sigqueueinfo(2)
