multithreading

Is there an attribute to mark the class or method to be thread safe in .NET?

In .NET how can I know if a class or method is thread safe or not? Is it by default not thread safe? ...

Threading and ArcGIS

Hi! I have just stumbled across the Backgroundworker object, and it seems like the tool I'm looking for to make my GUI responding while performing calculations. I am writing IO plugins for ArcGIS. I am doing some data processing outside ArcGIS, which works fine using the backgroundworker. But when I'm inserting the data into ArcGIS, th...

After execvp returns, why doesn't my program pick up where it left off?

I have a block of code like this that runs as a child thread: if(someVar == 1){ doSomeStuff; _exit(0) } else execvp(*(temp->_arguments), temp->_arguments); printf("I'm done\n"); When I run the program with someVar == 1, I understand that the _exit(0) call kills my thread. However, when it's set to 0, why doesn't the program contin...

What's wrong in terms of performance with this code? List.Contains, random usage, threading?

I have a local class with a method used to build a list of strings and I'm finding that when I hit this method (in a for loop of 1000 times) often it's not returning the amount I request. I have a global variable: string[] cachedKeys A parameter passed to the method: int requestedNumberToGet The method looks similar to this: List...

Java - If statement with String comparison fails

I really don't know why the if statement below is not executing: if (s == "/quit") { System.out.println("quitted"); } Below is the whole class. It is probably a really stupid logic problem but I have been pulling my hair out over here not being able to figure this out. Thanks for looking :) class TextParser extends Thread { ...

Logging and Synchronization

I have just written my own logging framework (very lightweight, no need for a big logging framework). It consists of an interface ILogger and a number of classes implementing that interface. The one I have a question about is TGUILogger which takes a TStrings as the logging target and synchronizes the logging with the main thread so that...

Are there any good beginner tutorials for threads in windows? C++

Looking for a good site or book that explains windows threads, preferably for a beginner. Maybe has a example program to run, etc.... ...

Run external program from Java, read output, allow interruption

I want to launch a process from Java, read its output, and get its return code. But while it's executing, I want to be able to cancel it. I start out by launching the process: ProcessBuilder pb = new ProcessBuilder(args); pb.redirectErrorStream(true); Process proc = pb.start(); If I call proc.waitFor(), I can't do anything until the p...

Do I need to Dispose() or Close() an EventWaitHandle?

If I am using EventWaitHandle (or AutoResetEvent, ManualResetEvent) to synchronise between threads then do I need to call the Close() or Dispose() methods on that event handle when I am done with it? EventWaitHandle inherits from WaitHandle, which implements IDisposable. And FxCop complains if I don't implement IDisposable on any class ...

Threading Best Practices

Many projects I work on have poor threading implementations and I am the sucker who has to track these down. Is there an accepted best way to handle threading. My code is always waiting for an event that never fires. I'm kinda thinking like a design pattern or something. ...

How can I easily chain two asynchronous requests together?

I've got some code that screen scrapes a website (for illustrative purposes only!) public System.Drawing.Image GetDilbert() { var dilbertUrl = new Uri(@"http://dilbert.com"); var request = WebRequest.CreateDefault(dilbertUrl); string html; using (var webResponse = request.GetResponse()) using (var receiveStream = webResponse...

pthread_cond_timedwait returning immediately

I'm having a strange problem. I have the following code: dbg("condwait: timeout = %d, %d\n", abs_timeout->tv_sec, abs_timeout->tv_nsec); ret = pthread_cond_timedwait( &q->q_cond, &q->q_mtx, abs_timeout ); if (ret == ETIMEDOUT) { dbg("cond timed out\n"); return -ETIMEDOUT; } dbg calls gettimeofd...

Overriding python threading.Thread.run()

Given the documentation at http://docs.python.org/library/threading.html which states for Thread.run(): You may override this method in a subclass. The standard run() method invokes the callable object passed to the object’s constructor as the target argument, if any, with sequential and keyword arguments taken from the args and kwar...

Threading in Java: How to lock an object?

Hi, The following Function is executing in its own thread: private void doSendData() { try { //writeToFile(); // just a temporary location of a call InetAddress serverAddr = InetAddress.getByName(serverAddress); serverAddr.wait(60000); //Log.d("TCP", "C: Connecting..."); Socket socket ...

How to update GUI from another thread in C#?

What is the simplest way to update an label from another thread? My problem: I have a winform(thread1), from that I'm starting another thread(thread2). While thread2 is processing some files I would like to update a label on the winform, with status from thread2. How can I do that? ...

Any Tips on Threading Considerations + Design for following cases

I'm writing a class library that will offer some asynchronous processing, and want to try and avoid running into threading issues later on down the line. So I'm after any suggestions people can make to avoid running into issues later on, and instead start with a good design. Some of the situations that I can see that might cause problem...

Is Threading not working properly in Nunit?

I think that nunit isn't function properly when threading code is involved: Here's the sample code: public class multiply { public Thread myThread; public int Counter { get; private set; } public string name { get; private set; } private Object thisLock = new Object(); ...

lock statement not working when there is a loop inside it?

See this code: public class multiply { public Thread myThread; public int Counter { get; private set; } public string name { get; private set; } public void RunConsolePrint() { lock(this) { RunLockCode("lock"); } } private vo...

How would YOU do/write this homework assignment? (theoretical)

I'm not asking for anyone to do this homework for me, but I bring it up because it's a very good practical introduction to C# and threading, but at the same time I feel it's perhaps a little too simple. Is this really the best way to teach threading? what key threading concepts are "lost" in this exercize, what would new programmers u...

C# Synchronized object - duplicate code with writing accessors

I like to use objects which sync itself using a private object which is locked when the property is changed. Is there any generic way to achieve this? My code looks always like this for each property (with one locker object) private Object locker = new Object(); private int x; public int X { get {return x;} set{ ...