program hangs in exit()

[Saurabh Desai <sdesai austin ibm com>]

The following program hangs during final exit()
using NPTL on RH9. It works using Linuxthreads.
The fgets() blocks while holding stdin->_lock and
during exit(), _IO_cleanup() also tries to acquire
same lock. Under Linuxthreads, the pthread_handle_exit() 
calls __fresetlockfiles() which resets all file locks. 
This is missing under NPTL.

- Saurabh

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

void *th_routine(void *arg)
{
        char buf[128];

        fgets(buf, sizeof(buf), stdin);
        return NULL;
}

main(int ac, char **av)
{
        pthread_t th;
        int rc;

        if ((rc = pthread_create(&th, NULL, th_routine, (void *)NULL)))
{
            printf("pthread_create failed, rc=%d\n", rc);
            exit(1);
        }
        sleep(1);
        printf("main: about to exit\n");
}