undefined reference to `_SetTextColor@8'

Im new to open gl, and im having some troubles:

when i try to run this code:

Code:

Code:

#pragma comment(linker, "/subsystem:windows")
/*	Pre-processor directives*/
#include <windows.h>
/*	Windows Procedure Event Handler*/
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	PAINTSTRUCT paintStruct;
	/*	Device Context*/
	HDC hDC; 
	/*	Text for display*/
	char string[] = "Hello, World!"; 
	/*	Switch message, condition that is met will execute*/
	switch(message)
	{
		/*	Window is being created*/
		case WM_CREATE: 
			return 0;
			break;
		/*	Window is closing*/
		case WM_CLOSE: 
			PostQuitMessage(0);
			return 0;
			break;
		/*	Window needs update*/
		case WM_PAINT: 
			hDC = BeginPaint(hwnd,&paintStruct);
			/*	Set txt color to blue*/
			SetTextColor(hDC, COLORREF(0x00FF0000));
			/*	Display text in middle of window*/
			TextOut(hDC,150,150,string,sizeof(string)-1);
			EndPaint(hwnd, &paintStruct);
			return 0;
			break;
		default:
			break;
	}
	return (DefWindowProc(hwnd,message,wParam,lParam));
}
/*	Main function*/
int APIENTRY WinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR     lpCmdLine,
                     int       nCmdShow)
{
	WNDCLASSEX  windowClass;		//window class
	HWND		hwnd;				//window handle
	MSG			msg;				//message
	bool		done;				//flag saying when app is complete
	/*	Fill out the window class structure*/
	windowClass.cbSize = sizeof(WNDCLASSEX);
	windowClass.style = CS_HREDRAW | CS_VREDRAW;
	windowClass.lpfnWndProc = WndProc;
	windowClass.cbClsExtra = 0;
	windowClass.cbWndExtra = 0;
	windowClass.hInstance = hInstance;
	windowClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
	windowClass.hCursor = LoadCursor(NULL, IDC_ARROW);
	windowClass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
	windowClass.lpszMenuName = NULL;
	windowClass.lpszClassName = "MyClass";
	windowClass.hIconSm = LoadIcon(NULL, IDI_WINLOGO);
	/*	Register window class*/
	if (!RegisterClassEx(&windowClass))
	{
		return 0;
	}
	/*	Class registerd, so now create window*/
	hwnd = CreateWindowEx(NULL,		//extended style
		"MyClass",			//class name
		"A Real Win App",		//app name
		WS_OVERLAPPEDWINDOW |		//window style
		WS_VISIBLE |
		WS_SYSMENU,
		100,100,			//x/y coords
		400,400,			//width,height
		NULL,				//handle to parent
		NULL,				//handle to menu
		hInstance,			//application instance
		NULL);				//no extra parameter's
	/*	Check if window creation failed*/
	if (!hwnd)
		return 0;
	done = false; //initialize loop condition variable
	/*	main message loop*/
	while(!done)
	{
		PeekMessage(&msg,hwnd,NULL,NULL,PM_REMOVE);
		if (msg.message == WM_QUIT) //check for a quit message
		{
			done = true; //if found, quit app
		}
		else
		{
			/*	Translate and dispatch to event queue*/
			TranslateMessage(&msg); 
			DispatchMessage(&msg);
		}
	}
	return msg.wParam;
}

Ive been searching for other posts regarding this problem, but what i found told me to delete the #include "stdafx.h" line, but when i delete this line i get these errors:
undefined reference to `_SetTextColor@8'
undefined reference to `GetStockObject@4'
undefined reference to `TextOutA@20'

How can i solve this 'undefined reference to `_SetTextColor@8'
problem??

PS> I'm a newbie, using Eclipse IDE and MINGW/MSYS toolchain.



help pls

Why is this thread so incredibly similar to this one?

I don't know Eclipse, but this line is the one that is, theoretically, in charge of what you want:

Code:

#pragma comment(linker, "/subsystem:windows")

If this is Eclipse's way of bringing in other libraries, then fine. If not, then you need to figure out what is Eclipse's way of bringing in other libraries, and use that to bring in the needed library (in this case, gdi32).

This line just ensures in-source that the program is linked not as a console app, but a win32 app. Nothing to do with libraries.

Also, it has nothing to do with Eclipse, only with the underlying compiler. I actually don't think MinGW GCC supports pragma comment.

Yeah, I don't know why I thought Eclipse had a compiler of their own underneath it.

@CornedBee : Yes this thread is similar to the one you linked to..., but I was asked to open a new thread since the other is too old, you'll see that in the last post.

Indeed Eclipse ingnores the #pragma line.
It is stated in the build warnings.
In the other thread there is also some comment about linking some libraries, so that might be the problem.
The problem is that I don't know how to link other libraries, and what libraries to link...

Anyone got a clue on how I do that in Eclipse or in code?

A quick check of the eclipse documentation suggests they use makefiles to control compilation; do you have something called "Makefile" in your directory? If so, find the rule for this target and add "-lwindows -lgdi32" to the end of it.

EDIT: Or if it's not a makefile project: http://help.eclipse.org/indigo/index...al_pns_lib.htm

Hi tabstop,

Thanks so far.
It's a non-makefile project. So I went to the form as in the help you pointed to....
So what exactly do I need to fill in libraries form? I can enter a library, or one tab further a library path. When I click on library, it asks me to add a file. Would this be a .dll from the system dir. or something like that?



PS. As you might notice this is my first time doing such things, I'm a complete noob on this subject....

OK, forget the last comment.
I enterred gdi32 in the library list, that did the trick.

Since I'd like to learn something from this, can someone explain what I'm actually doing by this. Yeah.... Linking a library, but what does that mean in terms of the Building process....

If you go to MSDN, it will tell you which library each of your functions belong to. So yeah, you'll have to add those system libraries to your project.

ETA: So you're calling the function, so you have to actually at some point have the code that does what you want. That's what the libraries are, bunches of code that do things.

Maybe a stupid question, but why isn't such a (system) library always linked?
Does that result in extra time/effort for the linker/compiler, even when the functions are not called?

Because there are 11732 such libraries (perhaps a slight overestimate).

Originally Posted by 0_AintLifeGrand

.....
Since I'd like to learn something from this, can someone explain what I'm actually doing by this. Yeah.... Linking a library, but what does that mean in terms of the Building process....

Take a look here, cprogramming.com's very own explaination.

Originally Posted by tabstop

Because there are 11732 such libraries (perhaps a slight overestimate).

And, of course, there can be custom libraries--IE libraries YOU make. Obviously the compiler cannot be aware of all those libraries, so you have to help it find some code sometimes.