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pthread_cancel and pthread_mutex_lock


Hello!

>From reading the mailing list archives i found out that at one point in 
the pthreads-win32 library pthread_mutex_lock acted as a cancellation
point, but since then that was removed. I have a thread that needs to be
cancelled during a pthread_mutex_lock, so naturally i would have to set
the cancel type to PTHREAD_CANCEL_ASYNCHRONOUS as per the new behavior.
I'm not sure if pthread_mutex_lock can be asynchronously cancelled, but
i'm having a problem with code similar to this:

------------------
#include <pthread.h>
#include <stdio.h>

pthread_mutex_t inputLock;

void *t2(void *threadid) {
	pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL);
	printf("created \n");

	/* waits to be cancelled here */
	pthread_mutex_lock(&inputLock);
	/* never gets here */
	printf("dead\n");
	return 0;
}

int main() {
	pthread_t sender;
	int i;

	/* initialize and lock mutex */
	pthread_mutex_init(&inputLock, NULL);
	pthread_mutex_lock(&inputLock);

	pthread_create(&sender, NULL, t2, NULL);

	/* psuedo sleep function */
	for(i = 0;i <10000000; i++) {}

	printf("slept and thread created\n");

	/* cancel thread and wait for termination */
	pthread_cancel(sender);
	pthread_join(sender, NULL);

	/* check if thread was cancelled */
	printf("successfully canceled thread\n");

	/* test lock for continued operation */
	pthread_mutex_unlock(&inputLock);
	pthread_mutex_lock(&inputLock);

	/* signify correct execution */
	printf("all done\n");
	
	return 0;
}

----------

On FreeBSD the code executes correctly, at least i assume it is the
correct behavior of a pthreads implementation. On windows it just
freezes after it prints "created". I appreciate any help! thank you!
-rian


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