Re: [PATCH v3] posix-timers: add multi_clock_gettime system call

From: Richard Cochran
Date: Mon Jan 15 2024 - 18:46:24 EST


On Mon, Jan 15, 2024 at 05:49:32PM +0200, Sagi Maimon wrote:

> Thanks for your notes, all of them will be done on the next patch (it
> will take some time due to work overload).

No hurry, glad you are keeping this going...

> The only question that I have is: why not implement it as an IOCTL?
> It makes more sense to me since it is close to another IOCTL, the
> "PTP_SYS_OFFSET" family.

I've often needed other clock offsets, like CLOCK_REALTIME - CLOCK_MONOTONIC.

Those don't have a character device, and so there is no way to call
ioctl() on them. That is why I'd like to have a system call that
handles any two clock_t instances, using the most accurate back end
based on the kinds of the two clocks.

Thanks,
Richard