Python closethreadfrom outside

A thread can also terminate early, as was demonstrated in last week’s Lesson. This trick is used to capture a thread’s return value.

It’s important that you not use pthread_cancel() haphazardly. You don’t want to suddenly cancel a thread in the middle of something, which may create an unstable or undesirable condition.

The first prompt’s text (Line 29) is updated to direct the user to press Enter to kill the thread. The pthread_cancel() function removes it, followed by output confirming that the thread is dead. Here’s a sample run:

End threadmeme

The following update to the code adds the pthread_cancel() function to terminate the thread after the first Enter key prompt:

To protect a thread from cancelation, refer to the pthread_setcancelstate() and pthread_setcanceltype() functions. You can also use the pthread_testcancel() function to insert a safe cancellation point within a thread’s code.

End threadpython

Another way to rub out a thread is to kill it off. The pthread_cancel() function handles the assassination. Its sole argument is the pthread_t value of a launched and running thread. Poof! The thread is gone.

Close thethreadmeaning

A good web page for further research on the topic of multithreaded programming in C is found here:Multithreaded Programming Guide from Oracle.

A thread ends in one of three ways: natural causes, an early exit, or sudden death. Yes, it’s exciting, but no more than any aspect of programming. I suppose the normal way for a thread to die is along with its parent program. Because the thread is part of the same overall process, when the main program terminates so do any spawned threads.

The following code launches a thread that runs an endless loop. The main program pauses twice: once just because and a second time to quit.