NAME

       pthread_kill - send a signal to a thread

LIBRARY

       POSIX threads library (libpthread, -lpthread)

SYNOPSIS

       #include <signal.h>

       int pthread_kill(pthread_t thread, int sig);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       pthread_kill():
           _POSIX_C_SOURCE >= 199506L || _XOPEN_SOURCE >= 500

DESCRIPTION

       The  pthread_kill()  function sends the signal sig to thread, a thread in the same process
       as the caller.  The signal is asynchronously directed to thread.

       If sig is 0, then no signal is sent, but error checking is still performed.

RETURN VALUE

       On success, pthread_kill() returns 0; on error, it returns an error number, and no  signal
       is sent.

ERRORS

       EINVAL An invalid signal was specified.

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌───────────────────────────────────────────────────────────────┬───────────────┬─────────┐
       │Interface                                                      │ Attribute     │ Value   │
       ├───────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │pthread_kill()                                                 │ Thread safety │ MT-Safe │
       └───────────────────────────────────────────────────────────────┴───────────────┴─────────┘

STANDARDS

       POSIX.1-2001, POSIX.1-2008.

NOTES

       Signal  dispositions  are process-wide: if a signal handler is installed, the handler will
       be invoked in the thread  thread,  but  if  the  disposition  of  the  signal  is  "stop",
       "continue", or "terminate", this action will affect the whole process.

       The  glibc  implementation  of  pthread_kill() gives an error (EINVAL) on attempts to send
       either of the real-time signals used internally by the NPTL threading implementation.  See
       nptl(7) for details.

       POSIX.1-2008 recommends that if an implementation detects the use of a thread ID after the
       end  of  its  lifetime,  pthread_kill()  should  return  the  error  ESRCH.    The   glibc
       implementation returns this error in the cases where an invalid thread ID can be detected.
       But note also that POSIX says that an attempt to use a thread ID whose lifetime has  ended
       produces  undefined  behavior,  and  an  attempt  to use an invalid thread ID in a call to
       pthread_kill() can, for example, cause a segmentation fault.

SEE ALSO

       kill(2),  sigaction(2),  sigpending(2),  pthread_self(3),  pthread_sigmask(3),   raise(3),
       pthreads(7), signal(7)