__libc_lock_lock (&lock);
__libc_lock_lock (lock);
weak_alias (__lckpwdf, lckpwdf)int__ulckpwdf (){  int result;  if (lock_fd == -1)    /* There is no lock set.  */    result = -1;  else    {      /* Prevent problems caused by multiple threads.  */      __libc_lock_lock (&lock);      result = close (lock_fd);      /* Mark descriptor as unused.  */      lock_fd = -1;      /* Clear mutex.  */      __libc_lock_unlock (lock);    }  return result;}