multitasking

I'm wondering if it's possible to implement preemptive multitasking of native code within a single process in user space on Linux. (That is, externally pause some running native code, save the context, swap in a different context, and resume execution, all orchestrated by user space but using calls that may enter the kernel.) I was thinking this could be done using a signal handler for SIGALRM , and the *context() family but it turns out that the entire *context() family is async-signal-unsafe so that approach isn't guaranteed to work. I did find a gist that implements this idea so apparently

Am I missing something here with Multitasking feature. I know we can execute a task in background, but what I really need is that task continues execution when app goes in background. So what I need is different than starting a new task in background. If images are being loaded in a view and user presses the home button to make the app go in background, I want that images continue to load and when user makes the app active again, he can see all the loaded images. How can this be done? Thanks a lot. Documentation on background task execution is on Apple's site in the iPhone Application

I know this is possible as Tapbots Pastebot does this. I am trying to grab the UIPasteboard when my iPhone app is running in the background and add it to a UITableView just as Pastebot does but I am also trying to shorten the link, if its a URL and copy that back to the UIPastboard so its ready for the user to paste anywhere. Now Pastebot apparently runs in the background by playing an audio file for 10 minutes. I have set up the NSNotificationCenter like so in the applicationDidFinishLaunching [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector

I have an app that fetches content in the background with the help of Background Fetch. So if a Background Fetch should take place my application:performFetchWithCompletionHandler: method is called. In this method I use NSURLConnection to fetch content asynchronous. In my current implementation I only start the request and then call the completionHandler with UIBackgroundFetchResultNewData . I know that this cannot be right. So my question is, how do I correctly call the completionHandler when the async request finishes in connection:didReceiveData: method. You're right — you should call the

As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Multitasking seems to be a disaster at times when big projects crashes due to shared mutation of I would say shared resources are accessed by multiple threads. It becomes very difficult to debug and trace the origin of bug and what is causing it. It made me

I want to create a program to crawl and check my websites for http errors and other things. I want to do this with multiple threads that should accept parameters like the url to crawl. Although I want X threads to be active there are Y Tasks waiting already to be executed. Now I wanted to know what is the best strategy to do this: ThreadPool, Tasks, Threads or even something else? Here's an example that shows how to queue up a bunch of tasks but limit the number that are concurrently running . It uses a Queue to keep track of tasks that are ready to run and uses a Dictionary to keep track of