tkill, tgkill - send a signal to a thread
int tkill(int tid, int sig); int tgkill(int tgid, int tid, int sig);
Note: There is no glibc wrapper for
tkill(); see NOTES.
tgkill() sends the signal
sig to the thread
with the thread ID
tid in the thread group
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.
On success, zero is returned. On error, -1 is returned, and
errno is set appropriately.
The RLIMIT_SIGPENDING resource limit was reached and
sig is a real-time signal.
Insufficient kernel memory was available and
sig is a
An invalid thread ID, thread group ID, or signal was specified.
Permission denied. For the required permissions, see kill(2).
No process with the specified thread ID (and thread group ID) exists.
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