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javascriptdeadlockinfinite-loop

JavaScript deadlock

Here I saw JavaScript deadlocks and this code:

var loop = true,
block = setTimeout(function(){loop = false}, 1);
while(loop);

It's definitely infinite loop and causes to browser freezing. It's said that deadlock is created when one operation wait another one to be executed and vice-versa.
My question is, except that, what kind of situations deadlock occurs and the ways to avoid them?

Solution

  • That's not a deadlock, just an infinite loop, you can't have a deadlock in JavaScript as you can't have more than one thread accessing your data.

    What happens here is that as your loop never ends and the js engine being mono-thread (regarding your script), the scheduler never calls the callback you give to setTimeout. In fact you would have had exactly the same behavior without the second line.