x/sys/windows: Expose timeBeginPeriod and timeEndPeriod

[johnrs]

Problem: A breaking change made in Go 1.16, 2.5 years ago, and is ongoing. It affects Windows users. See Issue #44343 for details and links to other issues for the same problem.

Discussion: This proposal would help to mitigate the problem. It would make it much easier for a user, unfamiliar with Windows system calls, to use timeBeginPeriod and timeEndPeriod, which have been identified as a workaround. Using these, a user could manually set the system clock to the desired resolution, typically 1ms or 15.6ms. This workaround has been determined to not interfere with the current Go runtime. It has been tested by multiple people and found to work.

[qmuntal]

I'm in favor of doing this, as @johnrs mentioned, it will help mitigating #44343.

@golang/windows

[ianlancetaylor]

In general it's always fine to add new functions that call standard Windows functions to x/sys/windows. That can be done without a proposal. A proposal is only required if it's not a standard Windows function, or if the function can't be called in an ordinary way (perhaps it requires a special data structure or something). That doesn't seem to be the case here, so taking this out of the proposal process. Thanks.

[qmuntal]

Thanks for the clarification @ianlancetaylor.

@johnrs do you feel like submitting a CL with the proposed changes?

[johnrs]

@qmuntal It would be better if you did. My knowledge of Windows system calls and how Go uses them isn't that strong.

[gopherbot]

Change https://go.dev/cl/515915 mentions this issue: windows: add TimeBeginPeriod and TimeEndPeriod syscalls