How to include libraries when compiling with Visual Studio on command line?

Question

I'm attempting to build a program with Visual Studio 2008 on the command line. After reading Walkthrough: Compiling a Native C++ Program on the Command Line. I tried the following:

Run the vcvaralls.bat to setup the enviroment:

"C:\Program Files (x86)\Microsoft Visual Studio 9.0\VC\vcvarsall.bat"

Wrote this simple C++ application:

#define _WIN32_WINNT 0x501
#include <windows.h>
INT WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
                   LPSTR lpCmdLine, int nCmdShow)
{
    MessageBoxA(0,"Hello","Hello",MB_OK);

    return 0;
}`

And attempted to compile it:

cl /EHsc /GA simple.cpp

And this happens:

/out:simple.exe
simple.obj
simple.obj : error LNK2019: unresolved external symbol __imp__MessageBoxA@16 referenced in function _WinMain@16
simple.exe : fatal error LNK1120: 1 unresolved externals

Which leads me to believe that I need to include user32.lib or similar. I cant figure out from the visual studio manuals how to do that.

Answer 1

Yes, to use MessageBox you need to link at least with User32.lib, as shown here . Use:

cl /EHsc /GA /MT simple.cpp User32.lib

/MT chooses the Run-time library. In this example I used multi-threaded static library.

Answer 2

You're correct, MessagBoxA is defined in User32.lib and you need to link your code with it. You can provide the linker options to the CL compiler and it will pass it to the linker. All you need to do is to add the User32.lib to your compilation string: cl /EHsc /GA simple.cpp User32.lib