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If you want a real time operating system, you will probably have to write your own. 
If you can keep your head while those about you are losing theirs, perhaps you don't understand the situation.
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You can be fairly precise with Windows, XP to 10, but you have to know how to do it.
Mostly you can set the global scheduling timer (not the best choice but workable on embedded systems) down to 1ms. Under 1ms forget thread sleeping and go for a busy form of waiting.
It is a soft real time but it is cost effective.
GCS d--(d+) s-/++ a C++++ U+++ P- L+@ E-- W++ N+ o+ K- w+++ O? M-- V? PS+ PE- Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- r+++ y+++* Weapons extension: ma- k++ F+2 X
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Yeah, NT had a 9.8 something ms granularity, that was the smallest wait.
You can as you say change this on later OSs, but it isnt recommended.
What I have done is to use a loop count in code (the code can work out the number to count up to to for a given time period at start up).
It is interruptible, you can set the code priority (critical section etc), and it gave quite accurate timing in the end. Of course it does depend on how much hardware activity there is that really will steal the CPU from you. But in general it was pretty good.
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Munchies_Matt wrote: What I have done is to use a loop count in code (the code can work out the number to count up to to for a given time period at start up).
That's a powerful solution. Mine was simpler for simpler needs, it broke down the wait time in time slices and used the usual SleepEx to save CPU time, in the remainder it used a stupid loop that checked the high precision timer - after all this time slice has been assigned to my thread, might as well use it.
But the problem was simpler, I just had to prevent two data packets being sent back-to-back forcing a delay, because the target device would get FUBAR if a request would arrive while it was still processing the previous one.
GCS d--(d+) s-/++ a C++++ U+++ P- L+@ E-- W++ N+ o+ K- w+++ O? M-- V? PS+ PE- Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- r+++ y+++* Weapons extension: ma- k++ F+2 X
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den2k88 wrote: I just had to prevent two data packets being sent back-to-back forcing a delay, because the target device would get FUBAR if a request would arrive while it was still processing the previous one
Yeah, hardware can be like that! 
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Quote: fairly precise
OK for Horseshoes and hand grenades.
If you can keep your head while those about you are losing theirs, perhaps you don't understand the situation.
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And cheap industrial systems with real time constraints but still in the "mechanical actuation" range of values  Basically horseshoes and handgrenades.
A 155mm Howitzer *is* fairly precise, after all.
GCS d--(d+) s-/++ a C++++ U+++ P- L+@ E-- W++ N+ o+ K- w+++ O? M-- V? PS+ PE- Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- r+++ y+++* Weapons extension: ma- k++ F+2 X
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As you have discovered, this is not very accurate. A better approach is to have a recurring timer that calls your callback every TBD.
If important, you would still need to call a clock API in your callback in order to determine when it was actually called, as opposed to when it was scheduled.
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
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Do you mean a WM_TIMER? I thought they were even less accurate.
Care to elaborate a bit?
M.D.V. 
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
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Thanks
I think I have found another possible alternative, see OP
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
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Sounds like it's really ticking you off...
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Sander Rossel wrote: Sounds like it's really ticking you off...
more pissing me off
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
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A reminder about "Them[^]"
| Ravings en masse^ |
|---|
| "The difference between genius and stupidity is that genius has its limits." - Albert Einstein | | "If you are searching for perfection in others, then you seek disappointment. If you are seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010 |
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I went to a few interviews last year while hunting around. When asked a newbie programming question, I told them, don't ask me questions you can google the answer for. I was met with silence as they reviewed their questions and realized pretty much all of them were google-able. 
Latest Article - A 4-Stack rPI Cluster with WiFi-Ethernet Bridging
Learning to code with python is like learning to swim with those little arm floaties. It gives you undeserved confidence and will eventually drown you. - DangerBunny
Artificial intelligence is the only remedy for natural stupidity. - CDP1802
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I start by asking newbie questions all the time, only gradually moving up to the level that's required. This is regardless of what the interviewee claims they're capable of.
You wouldn't believe how many candidates claim something insane like "it's my algorithm that actually routes all the planes across the world in real-time", then fail to solve fizzbuzz when asked to.
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Rajesh R Subramanian wrote: I start by asking newbie questions all the time,
I actually don't ask any questions at all. I ask them to tell me about what they have done. If it is then unclear that they know what they are talking about, then I will ask some questions.
Social Media - A platform that makes it easier for the crazies to find each other.
Everyone is born right handed. Only the strongest overcome it.
Fight for left-handed rights and hand equality.
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Googleable questions would filter out 90% of question posters from QA.
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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As someone who is always moving from place to place, I kinda specialise in asking stupid questions.
The difference is that it's pretty obvious that I'm not stupid, and I'm just asking about things that I don't know yet.
It's when the person asking stupid questions is actually stupid that you have a problem.
I wanna be a eunuchs developer! Pass me a bread knife!
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There are no stupid questions, only stupid people. 
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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Gratitude is initially based around mixed-grade mishap (7)
modified 24-Apr-19 4:12am.
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TRAGEDY
Gratitude (thank you) initially = TY
around mixed grade = RAGED
Mishap = TRAGEDY
Whenever you find yourself on the side of the majority, it is time to pause and reflect. - Mark Twain
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Yep, well done 
Over to you.
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98. Philosopher - cold unknown card (5)
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