locking

I have two threads in python (2.7). I start them at the beginning of my program. While they execute, my program reaches the end and exits, killing both of my threads before waiting for resolution. I'm trying to figure out how to wait for both threads to finish before exiting. def connect_cam(ip, execute_lock): try: conn = TelnetConnection.TelnetClient(ip) execute_lock.acquire() ExecuteUpdate(conn, ip) execute_lock.release() except ValueError: pass execute_lock = thread.allocate_lock() thread.start_new_thread(connect_cam, ( headset_ip, execute_lock ) ) thread.start_new_thread(connect_cam, (

Is there anyway that we can detect when the system/screen gets locked and notify some event to trigger in Ubuntu ? There is a possibility to be notified when the screen becomes locked/unlocked with DBus, this is reference on GnomeScreensaver showing the basics of it. I am not DBus expert, but there are bindings for python, so you can listen for DBus events in python. Combinig the two, you should be able to get what you want:-). Here is a python-dbus programming tutorial on wikibooks. 来源： https://stackoverflow.com/questions/2395579/detect-workstation-system-screen-lock-using-pythonubuntu

Do queries executed with the same SQLAlchemy session object use the same underlying connection? If not, is there a way to ensure this? Some background: I have a need to use MySQL's named lock feature, i.e. GET_LOCK() and RELEASE_LOCK() functions. As far as the MySQL server is concerned, only the connection that obtained the lock can release it - so I have to make sure that I either execute these two commands within the same connection or the connection dies to ensure the lock is released. To make things nicer, I have created a "locked" context like so: @contextmanager def mysql_named_lock

While I was reading about ReaderWriterLockSlim lock mechanism , There was this guy who suggested that Interlock Functions can be used for a finer locking Also, I found here another answer from Marc : ...Writes make their change to a cloned copy, then use Interlocked.CompareExchange to swap the reference (re-applying their change if another thread mutated the reference in the interim). Well , Currently all I know about Interlocked object , is that it is used (in a multithreaded environment) to do atomic additions , compare , compareExchange operations. (and I know how to use it) But ( and here

To put it simple: a swing app that uses sqlitejdbc as backend. Currently, there's no problem launching multiple instances that work with the same database file. And there should be. The file is locked (can't delete it while the app is running) so the check should be trivial. Turns out not. File f = new File("/path/to/file/db.sqlite"); FileChannel channel = new RandomAccessFile(f, "rw").getChannel(); System.out.println(channel.isOpen()); System.out.println(channel.tryLock()); results in true sun.nio.ch.FileLockImpl[0:9223372036854775807 exclusive valid] No matter whether the app is running or