multitasking

Currently, i am having difficulties to understand multi-tasking using async and await pattern. In order test a case, i have written following code to understand some basics; public partial class MainWindow : Window { public MainWindow() { InitializeComponent(); } private int global_int = 10; public async Task<int> RunAsyncTask() { // This method runs asynchronously. await Task.Run(() => Calculate()); return global_int; } private int Calculate() { Console.WriteLine("Ticket count: " + --global_int); return global_int; } private async void Start_Button_Click(object sender, RoutedEventArgs e) {

I am trying to take advantage of iPhone 4 multitasking feature. I want to run app in background and frequently send http request to send/receive data, is it possible? Surprisingly, there is actually very little time-slicing going on in the "multi-tasking" iOS 4.x. What goes on instead is really just application suspend / resume. When an application is sent to the background upon the user tapping the home button, it will stop getting execute cycles after a short while (*). (*) There are a few exceptions. Applications which declare themselves as "VoIP providers", location-based apps, and music

I have a music player app which implements background audio. I’m trying to update the screenshot in the iOS7 multi-tasking switcher when the track changes. So, if I background the app during Song A, it finishes and Song B comes on, if I then go into the tray I’d like to see a screenshot showing Song B’s artwork, title, etc. I’ve done some digging and not managed to find any way to tell iOS to update short of implementing Background Fetch and going all out with that. Is there another means of doing this, something I can call to tell it to refresh it when my tracks change? Apple does not provide

I have to develop a kind of GPS navigation application that needs to constantly keep track of the position of the user, which is moving by car. In the specific, I don't have to display the current location on a map but just to record its position with the best possible precision in order to calculate the total distance traveled. Of course the application needs to continue its work in background if the user switch to another app, a phone call come in or something like that… From the tests I have made and from what I have learned from this useful post (and from the documentation ), it seems to

How can I check if thread has finished work in C++11 and above? I have been reading the documentation and I have written the following code: #include <iostream> #include <thread> void mythread() { //do some stuff } int main() { std::thread foo(mythread); if (foo.joinable()) { foo.join(); //do some next stuff } } joinable tells only that the thread has started work, but I would like to know how to write code to check if the thread has finished work. For example: #include <iostream> #include <thread> void mythread() { //do some stuff } int main() { std::thread foo(mythread); if (foo.finishedWork

I'm currently learning Assembly and I'm confused how the CPU registers work with Multitasking. So in a Multitasking System. CPU can pause the execution of a certain program at any time and run another program. So how are the register values preserved during this step ? Are the registers pushed to stack or any other way ? osgx how the CPU registers work with Multitasking. CPU basically may not work with multitasking, task switch may be (and is) implemented in software. Some CPU (intel x86) may have hardware state (TSS https://en.wikipedia.org/wiki/Task_state_segment ) and TR (task register) to

I am playing music using AVAudioPlayer in background. The problem is: if there is a incoming calling interrupts the player, it will never resume unless switch to foreground and do it manually. The code is simple, to play it in background: [[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryPlayAndRecord error: nil]; [[AVAudioSession sharedInstance] setActive: YES error: nil]; url = [[NSURL alloc] initFileURLWithPath:...]; audio_player = [[AVAudioPlayer alloc] initWithContentsOfURL: url error:NULL]; audio_player.delegate = self; bool ret = [audio_player play]; delegate to handle