NAME
pthread_join,
pthread_timedjoin_np —
wait for thread termination
LIBRARY
library “libpthread”
SYNOPSIS
#include
<pthread.h>
int
pthread_join(pthread_t
thread, void
**value_ptr);
#include
<pthread_np.h>
int
pthread_timedjoin_np(pthread_t
thread, void
**value_ptr, const struct
timespec *abstime);
DESCRIPTION
Thepthread_join()
function suspends execution of the calling thread until the target
thread terminates unless the target
thread has already terminated.
On return from a successful
pthread_join()
call with a non-NULL value_ptr argument, the value
passed to
pthread_exit()
by the terminating thread is stored in the location referenced by
value_ptr. When a
pthread_join() returns successfully, the target
thread has been terminated. The results of multiple simultaneous calls to
pthread_join() specifying the same target thread are
undefined. If the thread calling pthread_join() is
cancelled, then the target thread is not detached.
The
pthread_timedjoin_np()
function is equivalent to the pthread_join()
function except it will return ETIMEDOUT if target
thread does not exit before specified absolute time passes.
A thread that has exited but remains unjoined counts against [_POSIX_THREAD_THREADS_MAX].
RETURN VALUES
If successful, the pthread_join() and
pthread_timedjoin_np() functions will return zero.
Otherwise an error number will be returned to indicate the error.
ERRORS
The pthread_join() and
pthread_timedjoin_np() functions will fail if:
- [
EINVAL] - The implementation has detected that the value specified by thread does not refer to a joinable thread.
- [
ESRCH] - No thread could be found corresponding to that specified by the given thread ID, thread.
- [
EDEADLK] - A deadlock was detected or the value of thread specifies the calling thread.
- [
EOPNOTSUPP] - The implementation detected that another caller is already waiting on thread.
Additionally, the pthread_timedjoin_np()
function will fail if:
- [
ETIMEDOUT] - The specified absolute time passed while
pthread_timedjoin_np() waited for thread exit.
SEE ALSO
STANDARDS
The pthread_join() function conforms to
ISO/IEC 9945-1:1996 (“POSIX.1”). The
pthread_timedjoin_np() function is a
FreeBSD extension which first appeared in
FreeBSD 6.1.