Is is possible to call a function at a specific time in C++? For example, I would like to launch function doIt() when number_of_elapsed_milliseconds_since_application_start = x.
A cross-platform solution would be ideal.
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In pure C++ probably not, you will need some OS specific code. But you can use a platform-independent OS-wrapper, like Qt (although this could be a bit of an overkill for your quite simple problem).
EDIT: The simplest thing you could do, is actively blocking the program in a loop, that constantly polls the current time, until the deadline is reached, but that is probably not a very useful solution. So without threads or some event-driven timer (as every OS should have) you won't get very far.
Christian Rau
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I think every major OS has the `sleep` function, which is really all you need for nonstandard code. – Mooing Duck Apr 02 '12 at 18:20
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@MooingDuck Well, of course with the advent of C++11 my answer doesn't make that much sense. – Christian Rau Apr 02 '12 at 21:17
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Make a thread, put it to sleep until that time, and after the sleep, have it run that function.
George Kastrinis
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2+1, though I would note that we are not using real time OS, so the thread won't wake up at exactly the time scheduled, it'll be a bit off, how much depending on the current machine load. – Matthieu M. May 22 '11 at 11:55
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This is what's considered a 'CallBack' function or a 'listener'. More information on implementing it can be found here: http://www.cprogramming.com/tutorial/function-pointers.html
Hope that helps.
DKWII
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