Again, thank you for any help that you would possibly be able to show me in regards to this program. The timing resolution isn't that great, either, and often lies above 10ms. Other than that, I think that Stopwatch would probably be fine for what you're talking about. The library I like to port receives data from the serial port in a message based protocol. This clock is not affected by discontinuous jumps in the system time e.
I save every received byte in an object, which retrieves the current timestamp. Now to obtain the current time, subtracting from that a previously acquired time to obtain a TimeSpan value. More clocks may be implemented. We'll query that time before and after the code we're benchmarking, compute the difference and report that as the elapsed time. I will give a format and hopefully it will make responding to this so easy that it won't take more than 10 minutes of your time. Otherwise, the default libraries are sufficient.
I need a clean, clear-cut explanation of each method that needs to be used to time a specific block of code. Use when you need very fast, but not fine-grained timestamps. This kind of clock is called a monotonic clock. The nature of Windows thread scheduling will prevent you from getting timing information more accurate than to tens of milliseconds. Given some assumptions about the code it could be part of that is, assuming you've decided to create some sort of a time keeping class , yes.
Because the Win32 epoch begins at a midnight, the number of milliseconds passed so far today can be calculated from the filetime with a modulus operation. Would have rated it lower, but it does what it does fine. In particular, you probably would not want to poll the current time on a very frequent basis e. Or ar there better ways? Maybe the operation is some kind of clean-up task. Milliseconds Timer The uses constant units of milliseconds. The issue with me finding them is that I have to use the cmd prompt to fix them because it will assist me when I proceed into the industry, if only to have a better understanding of how the underlining structure of coding works. The interpretation of the corresponding time values and the effect on timers is unspecified.
Again, you have my never ending thanks! Or ar there better ways? It is not safe to assume the value returned by one function call has any meaning. And not a moment toooo soon! If you require the local time as configured by the Administrator, then you could use GetLocalTime. TheFemaleMagusOfDalaran and Nerdrage23 Call me crazy but I think that its made very poorly and is in dire need of an overhaul That's just some version of the Linux documentation. One of the other clocks should be used instead, if available. If you use gcc just make sure you add -lrt to your list of arguments. At the moment, while I understand how to get it to work from a logical stand-point, I am now hitting errors that I would like to have resolved before I proceed. You have a few good answers here, depending on what you're after.
. Relying on the wall-clock to find out how much time has passed since a previous event is a bug waiting to happen. . The register is available from user code with a bit of assembly. This will give you all the information and more you need on choosing the best one. Call me crazy but I think that its made very poorly and is in dire need of an overhaul to the presentation of the information.
The time on this clock will jump when changed. Especially if one is calculating elapsed times, one might have difficulties due to wrap-around at midnight. Use when you need very fast, but not fine-grained timestamps. There's on Windows, and some of them are more accurate than others and nobody has mentioned yet. Do keep in mind that in Windows tracking the time this way isn't going to provide a reliable distinction between a 12ms delay and a 44ms delay.
The accuracy may not be as good as the resolution implies, but nonetheless QueryPerformanceCounter is one of the better options for precision timing on Windows. Please take the bugs out that keep the app from launching and not working. Just remember that as the case with any profiling functions, this function adds a little overhead to your program, so make sure you disable the profiling code, using preprocessor commands for example, in the production release. Its time represents seconds and nanoseconds since the Epoch. The first argument to the function is a pointer to a timeval struct to fill.
See the sections that follow for discussion, caveats, and why this code requires so many ifdef's. The source is licensed under the Further reading Related articles at NadeauSoftware. Usually, there are more clocks provided, but I find these three the most useful as they allow to get the execution time spent in the system level, process level and the thread level. All my timing code contains is a single function seconds returning a double. Here is some code that works in Windows which I've used in a Open Watcom C project. A clock which may jump in time during runtime would lead to false result. I really don't want to change apps, but may have to so I can have a clock I can use.