Question

I am writing a program that can be loaded by another service (under our control), or by the logged-on user. The program needs to know if the window station is interactive in order to display dialogs. I know GetProcessWindowStation function, but this one returns a handle. Is there a way to find out?

Answer 1

The interactive window station is always winsta0. So you need to get the window station name to determine it. Here is some pseudo code:

wchar_t buffer[256] = {0};
DWORD length = 0;
GetUserObjectInformation(GetProcessWindowStation(), UOI_NAME, buffer, 256, &length);
if (!lstrcmp(buffer, "winsta0")) {
  // Interactive!
}

From http://msdn.microsoft.com/en-us/library/ms687096(VS.85).aspx:

The interactive window station, Winsta0, is the only window station that can display a user interface or receive user input