What is the Point of executing "sleep 0.1" about 70 times, instead of just executing "sleep 7"?

Resolution. sleep isn't guaranteed to end after exactly the specified time.

For example, your thread or process could be sitting in the run queue awaiting a cpu to come free when the actual sleep time runs out; so by the time control is returned to your thread, a few 10s, or 100s of microseconds have elapsed beyond the specified time. If you consistently sleep for 7 seconds, and the sleep consistently takes 7.001 seconds before returning control, your time-slots progressively slip a little more each time.

By looping over a smaller sleep and comparing against real-time; you may be a fraction out each time, but those fractions don't accumulate.

And you can tailor the sleep time used to balance cpu usage against accuracy.

Maybe you don't need the accuracy. But whenever you are attempting to time synchronise between systems; you should allow for discrepancies like these.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". I'm with torvalds on this
In the absence of evidence, opinion is indistinguishable from prejudice. Agile (and TDD) debunked

In reply to Re^3: How I unconditionally wait for data in 7 seconds? by BrowserUk
in thread How I unconditionally wait for data in 7 seconds? by sebastiannielsen2

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