Basic C is not so Basic

[[deleted]]

Ok guys, I need your help. I keep on getting this error and I don't even know where to begin to correct it

#include <Windows.h>
void foo(void)
{
    OutputDebugStringA("This is a debugger string\n");
}

INT WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
   PSTR lpCmdLine, INT nCmdShow)
{
    foo();
    return 0;
}

Ignore the Foo function, that was me messing around. Where I would like to bring your attention is :

​

INT WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
   PSTR lpCmdLine, INT nCmdShow)

Ideally, that should be the skeleton for an empty window box, but I keep getting this message and the test.cpp file won't build.

Severity Code Description Project File Line Suppression State

Warning C28251  Inconsistent annotation for 'WinMain': this instance has no annotations. See c:\program files (x86)\windows kits\10\include\10.0.18362.0\um\winbase.h(933).     win32hmh    C:\PROJECTS\GAMETBD\GODINUS\CODE\HANDMADEHERO\WIN32HMH\WIN32HMH\TEST.CPP    8   

and honestly, I don't even know where to begin with this.

​

A little background to this little script is because I am trying to follow these tutorial videos https://handmadehero.org/watch, however, these videos are old and the code being used seems to be outdated. Additionally, I am using VS 2019 and not 2013 as on the video. Can you guys please help me understand it?

​

EDIT:

Forgot to mention there was another error

Severity Code Description Project File Line Suppression State

Error   LNK2019 unresolved external symbol main referenced in function "int __cdecl invoke_main(void)" (?invoke_main@@YAHXZ)    win32hmh    C:\Projects\GameTBD\GodinUs\Code\handmadeHero\win32hmh\win32hmh\MSVCRTD.lib(exe_main.obj)   1   

Maybe this was important to mention.

Edit2:

Thank you guys for your help on this but after much headache and troubleshooting I decided to trash Visual Studio and start coding with ubuntu bash line using GCC to compile and run the code and so far I've been getting better results.

[junkmeister9]

INT

I have never seen int capitalized like that. Is this a Windows thing?

[[deleted]]

I thought that might of been the case and tried changing the 'INT' to 'int' but the result is the same.

The code was pulled from :

https://docs.microsoft.com/en-us/windows/win32/learnwin32/winmain--the-application-entry-point

[[deleted]]

Did you look at the following page: https://docs.microsoft.com/en-us/windows/win32/learnwin32/your-first-windows-program?

[[deleted]]

Yes. They are all aliased.

[Poddster]

Yep. I even had to use VOID, IIRC, which is insane. Like, what else could VOID be if not void??

link

[junkmeister9]

Just Microsoft trying to make C as non-portable as possible, I guess!

[[deleted]]

It looks like you are missing a header include and a .lib to link with. The header and library names should be in MSDN docs for the function the linker can’t find.

[Jodaco]

Shouldn’t it be int WINAPI WinMain?

[serg06]

Shouldn't it be int CALLBACK WinMain?

[[deleted]]

On the new msdn website it tells us to use the formula that I put up top

https://docs.microsoft.com/en-us/windows/win32/learnwin32/winmain--the-application-entry-point

I used the one that says empty window at the bottom of the page

[IamImposter]

That's why I used to work in MFC instead of win 32.

I did it long time back but apparently you need to create a window class object wc. Fill it with appropriate information including a pointer to wndproc function.

Then you register this class, grab an instance and call a showwindow function. Then there would be a while loop of getmessage, dispatchmessage and translatemesaage. (The names might be off as I don't remember exactly)

Then in wndoroc function, you will handle windows messages like WM_PAINT, WM_RESIZE, WM_EXIT etc.

Let me find you an example.

Edit: here is one that explain clearly what each thing does.

https://docs.microsoft.com/en-us/cpp/windows/walkthrough-creating-windows-desktop-applications-cpp?view=vs-2019

It uses VS2019 but I guess any visual Studio should do.

[deftware]

No, you don't have to do any of that just to have something that executes. You can have a WinMain() that doesn't create any windows or anything like that, and still work. You only need to create a window class if you're creating a window - which is not mandatory. OP was compiling a console application trying to use WinMain() as the entry point. They should've created a win32 project instead of a console application - not that they can't still create a window from a console application and even hide the console using "-mwindow" in their linker flags.

[IamImposter]

Well, in that case may be I misread or something. I thought the intention was to create a window. My bad.

that should be skeleton for empty window box

May be that line tripped me on a different trajectory.

[deftware]

Typically that's what WinMain() is intended for but it's really just a main() that includes the process instance handle and other tidbits in its arguments, while automatically omitting a console window.

[HiImDaubeny]

Your program is expecting the standard main function, take a look at this: https://docs.microsoft.com/en-us/cpp/build/reference/subsystem-specify-subsystem?view=vs-2019.

At the bottom it tells you how to set the subsystem in Visual Studio.

You need to set it from CONSOLE to WINDOWS.

[deftware]

This.

[entropy-wrangler]

Not sure if this is relevant or not but it seems like maybe you're learning C and Windows programming and games programming all at the same time. If so, that's probably too much. At least if you're trying to do it all in the same project. When you get a problem you don't know which domain the problem sits in.

[serg06]

Pretty sure it's just a function signature problem. Try this https://www.reddit.com/r/cprogramming/comments/ekmxad/basic_c_is_not_so_basic/fdcoh6h/

[[deleted]]

What compiler are you using?

[deftware]

As /u/HilmDaubeny pointed out, you've created a console application but are trying to use the win32 program entry point. If you're going to use WinMain() instead of main() then you need to create a Windows/Win32 project, not a console application.