pthread_kill man page


This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

pthread_kill — send a signal to a thread


#include <signal.h>

int pthread_kill(pthread_t thread, int sig);


The pthread_kill() function shall request that a signal be delivered to the specified thread.

As in kill(), if sig is zero, error checking shall be performed but no signal shall actually be sent.

Return Value

Upon successful completion, the function shall return a value of zero. Otherwise, the function shall return an error number. If the pthread_kill() function fails, no signal shall be sent.


The pthread_kill() function shall fail if:

The value of the sig argument is an invalid or unsupported signal number.

The pthread_kill() function shall not return an error code of [EINTR].

The following sections are informative.

Application Usage

The pthread_kill() function provides a mechanism for asynchronously directing a signal at a thread in the calling process. This could be used, for example, by one thread to affect broadcast delivery of a signal to a set of threads.

Note that pthread_kill() only causes the signal to be handled in the context of the given thread; the signal action (termination or stopping) affects the process as a whole.


If an implementation detects use of a thread ID after the end of its lifetime, it is recommended that the function should fail and report an [ESRCH] error.

See Also

kill(), pthread_self(), raise()

The Base Definitions volume of POSIX.1‐2008, <signal.h>