race-condition

Let's assume I'm using a Background Worker and I've the following methods: private void bw_DoWork(object sender, DoWorkEventArgs e) { finalData = MyWork(sender as BackgroundWorker, e); } private void bw_ProgressChanged(object sender, ProgressChangedEventArgs e) { int i = e.ProgressPercentage; // Missused for i Debug.Print("BW Progress Changed Begin, i: " + i + ", ThreadId: " + Thread.CurrentThread.ManagedThreadId); // I use this to update a table and an XY-Plot, so that the user can see the progess. UpdateGUI(e.UserState as MyData); Debug.Print("BW Progress Changed End, i: " + i + ", ThreadId:

I have a registration page that receives tokens ad parse them and login the user if the parameters apply. Between the time that i checked the token, to the time that i removed the token from the db, another user can use the same token to login. is there a way to make sure that specific range of lines of code will be executed with not interference, so i won't have race condition problem ? thanks update I have two servers. apache tomcat 6 red5 v0.9 (free java based flash media streaming and communication server) I'm writing a game application for Facebook. the game itself is written in adobe

I plan to use redis as an unique atomic id generator. However, my concern there might be simulatoneous web requests from multiple browsers. I was wondering, what is the common practice to make the following operations atomic? get id from redis if id is not found insert id as 0 into redis else store the id in a variable increase id by one store the new id back to redis If I were in desktop app or mobile app, I would use synchronized keyword in Java to avoid race condition . However, how about for a PHP web app? Assuming you're looking to generate sequential ids, you can use Redis and the INCR

I am battling with race condition protection in PHP. My application is written in symfony 1.4 and PHP locks session data until a page completes processing. I have a long running (~10 second) login script and I want to display a progress bar showing the user what is being done while they wait. (I want to actually display what is being done and not use a standard [faux] loading bar.) Whenever a script calls session_start() , PHP locks that user's session data until that script completes. This prevents my status check ajax calls from returning anything until the longer running script completes.

I'll present some code first since explaining is easier that way. Assume that mutexes are correctly used with the condition variables to keep it simple: // Thread 1 while(1) { conditionVariable.wait(); // Do some work } // Thread 2 while(1) { // Do some work conditionVariable.notify_one(); } // Thread 3 while(1) { // Do some work conditionVariable.notify_one(); } What I would like to achieve is that thread 1 is guaranteed to be waiting on the condition variable when thread 2 or Thread 3 notifies. As the code stands, there is a large gap between notify_one() and wait() in the form of some other