How do I create a timer run my program repeatedly? C++

Question

I want create timer in my program so that I can cause it to rerun every minute and I don't know how to do it in a C++ Application. In C# I could just create a timer but I'm struggling here now...

sleep(); is not an option because as far as I know it makes your program inactive for X seconds, I need my app to be active and working, calculating all the time. This is because my code is used to constantly input information into a MS Access table. I was able to create the necessary components of my code to connect and perform the insert/update to the table but this is just on of the many components to the code that I am creating. Please help me with this little (or big?) problem, I'm very new to C++ and learning ATM, but I am developing a fast learning curve. Thanks

Check this out. http://stackoverflow.com/questions/4855597/how-do-i-create-a-timer-do-something-every-x-seconds-minutes-hours — sealz, Jul 12 '11 at 19:36

score 1 · Answer 1 · answered Jul 12 '11 at 19:36

1

Every platform provides api for creating a timer, which will give you a callback usually after timer expires. You can just search for the api available on your platform.

If you are using windows use setTimer function.

answered Jul 12 '11 at 19:36

Alok Save

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I don't want to be too nitpicking, but since this is Windows C API, the correct case is SetTimer, not setTimer – Marius Bancila Jul 12 '11 at 21:47

score 1 · Accepted Answer · answered Jul 12 '11 at 19:38

1

I suppose you work on Windows, since you mentioned C#. So take a look at SetTimer, and if it is a MFC app, then look at CWnd::SetTimer.

answered Jul 12 '11 at 19:38

Marius Bancila

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I know that, but if I was to bet on that alone it was Windows I would have put the money with no problem; moreover, if you read below you can see a reference to MS Access. that means Windows :) – Marius Bancila Jul 12 '11 at 21:45

score 0 · Answer 3 · answered Jul 12 '11 at 19:37

If you're using C++ .NET, you can use the same Timer class(es) as C#, just use the C++ syntax (using gcnew instead of new, use the ^ for GC references).

Otherwise you could just have a loop:

while (should_keep_looping) {
  // do what you need to do

  // if necessary:
  sleep(1);
}

score 0 · Answer 4 · answered Jul 12 '11 at 19:38

0

See here: http://www.cplusplus.com/forum/beginner/317/

There is on built in "timer" in C++, and you are correct about the behavior of sleep(). The above thread describes a custom implementation.

answered Jul 12 '11 at 19:38

BlackJack

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score 0 · Answer 5 · answered Jul 12 '11 at 20:05

if you have a window you can use its message queue, as suggested by Als and Marius in their answers
you can use some task dispatcher and some timer to register a callback, e.g. functionality provided by Boost.Asio and its deadline_timer (example)
you can check if timer expired between your tasks manually as proposed in BlackJack's link
or you can create separate thread and make it call your callback when time came. Pros: you can use sleep() there and you callback will be called in parallel with your main thread. Cons: worry about synchronization

How do I create a timer run my program repeatedly? C++

5 Answers5