test_rw_locks shows how to use ACE_Local_RLock, ACE_Local_WLock, ACE_Remote_RLock, and ACE_Remote_WLock. Here are the options to test_rw_locks: % ./test_rw_lock -u -i ignore deadlock -n -r -d debug -s sleep during writes -t test_rw_locks spawns number of threads which perform the following algorithm: for { for acquire read lock for release read lock acquire write lock if (sleep during writes) sleep for 1 second release write lock } The output should show that multiple readers can acquire the lock for reading simultaneously (note that this also tests recursive acquisition.) When a writer lock is acquired, the output should show that no thread holds a reader lock. To run a test, simply type: % ./test_rw_lock This should show output as described above.