Interrupt Handler in C++ (Increment tick variable)

[steel anchor]

I am writing code for the OpenWatcom assembler to compile on DOS. I am looking to write an interupt handler which increments a private class variable _tick.

My compiler cannot find the header file for <thread>, so I figured the other way to write code that runs concurrently is by writing an interupt handler in either C++ or assembly to run alongside my code. Specifically interrupt 0x1c.

If I am super desperate, I could probably directly modify the Interrupt Vector Table with a far pointer? (I do not think this would be an ideal solution)

[pallid plover]

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