Function JOIN-THREAD

Syntax:

join-thread thread => multiple values

Arguments and values:

thread -> a thread object.

Description

Wait until thread terminates, or if it has already terminated, return immediately.

The return values of the thread function are returned.

Examples

(let ((thread (bt2:make-thread
               (lambda () (values 1 2 3)))))
  (bt2:join-thread thread))

=> 1, 2, 3

Exceptional situations:

If a thread is terminated by an unhandled condition, or by destroy-thread, then the condition abnormal-exit is signaled.

See also:

make-thread, abnormal-exit

Notes:

Due to how join-thread interacts with the dynamic environment established by make-thread, it is not safe to join with a thread that was created outside Bordeaux-Threads. For example, the following code has undefined behaviour and might very well corrupt the image:

(mapcar #'bt2:join-thread (bt2:all-threads))

Bordeaux-Threads can only record instances of thread termination due to unhandled conditions or the use of destroy-thread. In case of other ways to terminate a thread, such as throwing to an implementation-specific tag defined in the dynamic environment of the thread function, the behaviour of join-thread is undefined.