Quote:
Originally Posted by hazel
I remember once seeing some code in which a signal handler changed a global variable and the main loop just checked that variable synchronously each time it ran. The trouble is that if the loop is waiting anyway (say for user input) it might not get to checking for signals for quite some time.
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Probably Z80, Commodore 64? That was long time ago....
And it was about hardware interrupt which was (more or less) [something like] a function or subroutine which was simply called when the interrupt arrived. It made what it needed to do and then the program returned to the original point (before the interrupt) and did continue its execution.
It worked without threads, without multitask/multiuser/VM or other tricks. There was no protected RAM or protected mode....