IVRWatchdogProvider_Overview

Implement IVRWatchdogProvider when you want to run some code inside steam.exe. This means that when SteamVR is closed, the watchdog driver can still run as long as steam.exe process is still running. One example use case is to create a thread inside Init() function that will listen to a wake up event for a HMD. Check sample driver for how to do it.

Any driver that implements this interface must build for both 32-bit and 64-bit versions. steam.exe is responsible for loading the watchdog driver (in 32-bit), not vrserver.exe. You have to close both Steam and SteamVR before building the DLL.

One trick to build both 32-bit and 64-bit versions is to use Build ⇾ Batch Build function in Visual Studio.

Check this issue for more info: https://github.com/ValveSoftware/openvr/issues/1486