Windows SC.exe how to query control codes on a service

Question

What I Have Done

I am trying to implement ServiceBase.OnCustomCommand(int command) in a custom Windows Service called MyTestService, with custom command codes as done in this answer:

public enum MyCustomCommands { ExecuteScript = 128 };

I noticed it's common to start custom command values at 128.

---

I attempted to implement custom command codes like so:

public enum MyCustomCommandCodes
{
    Test1 = 1,
    Test2 = 2,
}

protected override void OnCustomCommand(int command)
{
    switch (command)
    {
        case (int)MyCustomCommandCodes.Test1:
            eventLog1.WriteEntry("Test1");
            break;
        case (int)MyCustomCommandCodes.Test2:
            eventLog1.WriteEntry("Test2");
            break;
        default:
            eventLog1.WriteEntry("default");
            break;
    }
}

I am calling OnCustomCommand using Window's command-line utility Service Control (SC).

When I enter sc control MyTestService 1, I found instead of calling case Test1, it actually stopped the service.

In my mind, this explains why people start command values at 128, it's to prevent overlap with codes already in use.

---

I would like to be able to see which control codes are already in use by a Windows service.

Two-part Question:

• Is there a way to query the list of all codes that are in use?
• If yes, is there also a way to query what each code actually does?

Answer 1

Per @madreflection's comment, which points out the ControlService function: https://learn.microsoft.com/en-us/windows/win32/api/winsvc/nf-winsvc-controlservice

User-defined control code range: 128 to 255.

And it also states why sc control MyTestService 1 stops the service, it's because 0x1 corresponds with the SERVICE_CONTROL_STOP control code.

---

This answers my question from a different direction, with a lookup table given by Microsoft.