It will work both on linux and on windows, i. If you want to use a third-party library use Boost, but a recent version. The time related std api are just a mess and I provide a summary here:.
So if you want portable code make your own solution or just use Boost 1. In windows for getting microsecond precesion you should use QueryPerformanceCounter winapi function. Here you can find how get that precesion using it. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Ask Question. Asked 10 years, 8 months ago. Active 2 years ago.
Viewed 83k times. Improve this question. Kara 5, 15 15 gold badges 49 49 silver badges 56 56 bronze badges. What are you using usleep for? Using select is a great idea. It is not terribly efficient, but then again when one is waiting, who cares. On the other hand, it is as portable as you can get. There exists no serious platform that doesn't have select. There's nothing obsolete about usleep. Add a comment. Active Oldest Votes. Improve this answer.
Adi Shavit Adi Shavit This only works on constant values obviously , and requires a using directive. See this answer for details. Don't know about VS one. Howard Hinnant Howard Hinnant k 49 49 gold badges silver badges bronze badges.
MS's implementation seems to boil down to Sleep or the equivalent , which takes milliseconds. The Sleep documentation explains that Sleep 0 can cause a deadlock when called from a threadpool thread under certain circumstances, and those circumstances were common in our test suite.
That sounds like it is worthy of a bug report. The implementation should round finer precisions up to the next sleep-able precision, not down. Summary: Sleep is well understood but poorly documented. A service thread can mimic sleeps at high resolution. Such a service thread coulb be esablished as a system wide service. Accuracy of the performance counter is to be looked at carefully. A calibration is required.
Arno Arno 4, 3 3 gold badges 35 35 silver badges 60 60 bronze badges. Not quite! This behavior changed starting with Windows Server This function causes a thread to relinquish the remainder of its time slice and become unrunnable for an interval based on the value of dwMilliseconds.
The system clock "ticks" at a constant rate. If dwMilliseconds is less than the resolution of the system clock, the thread may sleep for less than the specified length of time. If dwMilliseconds is greater than one tick but less than two, the wait can be anywhere between one and two ticks, and so on. To increase the accuracy of the sleep interval, call the timeGetDevCaps function to determine the supported minimum timer resolution and the timeBeginPeriod function to set the timer resolution to its minimum.
Use caution when calling timeBeginPeriod , as frequent calls can significantly affect the system clock, system power usage, and the scheduler. If you call timeBeginPeriod , call it one time early in the application and be sure to call the timeEndPeriod function at the very end of the application. After the sleep interval has passed, the thread is ready to run.
If you specify 0 milliseconds, the thread will relinquish the remainder of its time slice but remain ready. Note that a ready thread is not guaranteed to run immediately. Active 1 year, 4 months ago. Viewed k times. Improve this question.
T In C libraries are not imported. The compiler does not need them. The linker might link them, but only after the compiler is done. In C the compiler needs a prototype of a function to to use a function. Prototypes typically come in header files. Add a comment. Active Oldest Votes. Improve this answer. Daniel Selvan 7 7 silver badges 20 20 bronze badges.
I had not! Thank you! Would it be better to use the sleep function or time to create a delay? LandonZeKepitelOfGreytBritn: At least the C function time does not created a delay, at least not a well defined delay, based on the arguments passed. In every case, check the documentation.
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