On a sunny day (Sat, 23 Nov 2019 09:55:15 +0100) it happened "R.Wieser"
 wrote in :

>Hello all,
>
>I've got a few I2C modules (clock, temperature sensor, etc) that I would
>like to access using different programs.
>
>Under Windows the first program accessing certain hardware "takes
>possession" of it, causing other programs to be denied access.
>
>The question is: how do I allow multiple programs to access the same I2C
>bus, but not interfering with each other ?
>
>Or am I worrying about nothing, and the OS already sequentialises the
>request for me ?
>
>Regards,
>Rudy Wieser

Different tasks to the same i2c interface from user space is not possible in a
multitasker.
But you can make your own i2c interfaces on _any_ pins with some diodes,
I am doing that exactly here using two i2c busses:
 http://panteltje.com/panteltje/xgpspc/index.html

It is Linux so on windows you are on your own.
I never use the hardware i2c,
software is more than fast enough and that way I can port my code to any other
platform.

--- SoupGate-Win32 v1.05