a strange line of code

[johny145]

I am using some code which has the following lines in it:

		if (struct2->hwnd == ???)
		{
			return -1;
		}

mingw gives a warning (not even an error) about trigraphs, but i dont know what that means. Can anybody give some info on the meaning of "== ???", and how i can replace it?

[BradCantin]

the code is trying to compare the value of struct2->hwnd to ???, and if they are equal, then return -1.

my guess is that ??? was intended to be replaced by something down the line and whomever coded it put it in as a place holder and didn't fix it. You will have to contact the author of the code, or edit it yourself.

[dwks]

What other variables of the type struct2->hwnd are in scope? It might refer to one of those.

That is an invalid line of code as is.

Trigraph translation:

??= #
??> }
??< {
??! |

They're for computers that don't support #'s and stuff. You just put ??= in.

[dwks]

Also related are digraphs:

<: [
:> ]
<% {
%> }

There are more digraphs and trigraphs, but those are the only ones I've memorized.

[johny145]

I have seen the trigraphs on msdn and ??? is not defined there.

the file where this code is from is vstgui.cpp

LRESULT CALLBACK MouseProc (int nCode, WPARAM wParam, LPARAM lParam)
{
	if (nCode < 0)
		return CallNextHookEx (MouseHook, nCode, wParam, lParam);

	if (wParam == 522)
	{
		MOUSEHOOKSTRUCT* struct2 = (MOUSEHOOKSTRUCT*) lParam;
		if (struct2->hwnd == ???)
		{
			return -1;
		}
	}
	return CallNextHookEx (MouseHook, nCode, wParam, lParam);
}

Since this is pretty official stuff i cant believe the programmer just forgot to fill it.

[Thantos]

It is MSDN afterall.....

[Salem]

Can you post the actual URL of where the code came from?
It looks like an HTML/Browser problem with generating the page, or perhaps a problem copying some fancy HTML character back to ASCII in your code.

[johny145]

sure i can post it, but i dont think it is a mistake with copy+past
http://ygrabit.steinberg.de/users/yg...mon/vstgui.cpp

[anonytmouse]

The line in question is inside a conditional section. I think it is incomplete code. Have you tried downloading the SDK containing vstgui.cpp? Anyway, the aim of the code in question is to prevent the WM_MOUSEWHEEL notification reaching a specific window. So, as a quick fix, you can just comment it out and not use your mouse wheel.

[johny145]

After my initial trials using the code i found out this line of code is the least of my problems. The documentation for the usage of vst's is incomplete and incoherent at best. I am using msdn for some time now, and although i sometimes have problems finding the info i need, the documentation from steinberg isnt even remotely as good as msdn. After a couple of hours of frustrated trials i decided to let this rest for a while until i find the time and courage to start with it again.

The good thing about this all is that i appreciate msdn a lot more then before .

And thx to all who have replied in this thread .