[aoanevdus]

People write code that does sleep statements when waiting for something else to happen. It makes sense in some contexts. Think of it like async/await with an event loop. Except you are using the OS scheduler like your “event loop”. And you sleep instead of awaiting.

Now, if your language lacks the sleep statement or some other way to yield execution, what should you do instead when your program has no work to do? Actually, I don’t know what the answer is.

[dspillett]

Later versions of VB (4 and later IIRC) did have a sleep function, though many didn't bother using it and kept with their DoEvents loops instead (which would allow their own UI updates to process but still kept the CPU pegged as much as their process could). With earlier versions you could actually call the windows sleep API. Whether using the OS sleep() or the built-in function (itself just a wrapper around the OS sleep() function), it was worth calling DoEvents a couple of times first to ensure any progress information you'd updated on your UI had been processed, so the user can see it.

[liontwist]

Thanks for explaining.

(I disagree that you should be sleeping for any OS event, this is what blocking kernel events do automatically)