Windows how to get the process group of a process that is already running?

Question

I have a WPF application that starts a new process using Process.Start(ProcessStartInfo info).

How do I get the group process ID of the process so that

Answer 1

The documentation for GenerateConsoleCtrlEvent states (emphasis mine):

The identifier of the process group to receive the signal. A process group is created when the CREATE_NEW_PROCESS_GROUP flag is specified in a call to the CreateProcess function. The process identifier of the new process is also the process group identifier of a new process group.

So if your processes are in a group, the WPF application's PID should be the group ID.