Thread: Puzzled by this code

i got this sample of creating a window on borland cbuilderx

Code:

#include<windows.h>
#include<windows.h>
#ifdef _BORLANDC_
#pragma argsused
#endif
LRESULT CALLBACK WndProcedure(HWND hWnd, UINT uMsg,WPARAM wParam,LPARAM lParam);
int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,LPSTR
lpCmdLine,int nCmdShow)
{
HWND WinForm;
MSG WinMsg;
const char *Clsname="Win32Test";
const char *Wndname="GS Application";
HINSTANCE WinIns;
WinIns=hInstance;

WNDCLASSEX WndRegist;
        WndRegist.cbSize        = sizeof(WNDCLASSEX);
        WndRegist.style         = CS_HREDRAW | CS_VREDRAW;
        WndRegist.lpfnWndProc   = WndProcedure;
        WndRegist.cbClsExtra    = 0;
        WndRegist.cbWndExtra    = 0;
        WndRegist.hIcon         = LoadIcon(NULL, IDI_APPLICATION);
        WndRegist.hCursor       = LoadCursor(NULL, IDC_ARROW);
        WndRegist.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
        WndRegist.lpszMenuName  = NULL;
        WndRegist.lpszClassName = Clsname;
        WndRegist.hInstance     = WinIns;
        WndRegist.hIconSm       = LoadIcon(NULL, IDI_APPLICATION);
RegisterClassEx(&WndRegist);


WinForm=CreateWindow(Clsname,Wndname,WS_OVERLAPPEDWINDOW,100,100,500,300,NULL,NULL,WinIns,NULL);
  if(WinForm)
          {MessageBox(NULL,"Window successful created.","SystemMessage",MB_OK|MB_ICONINFORMATION);}
  else
          {MessageBox(NULL,"Error: Something happend,something bad ...","SystemMessage",MB_OK|MB_ICONWARNING);return 0;}

ShowWindow(WinForm,SW_SHOWNORMAL);
UpdateWindow(WinForm);
while( GetMessage(&WinMsg, NULL, 0, 0) )
       {
            TranslateMessage(&WinMsg);
            DispatchMessage(&WinMsg);
       }

return Msg.wParam;
}


LRESULT CALLBACK WndProcedure(HWND hWnd, UINT Msg,WPARAM wParam, LPARAM lParam)
{
    switch(Msg)
    {
    case WM_CREATE:
        return 0;
    case WM_DESTROY:
        PostQuitMessage(WM_QUIT);
        break;
    default:
        return DefWindowProc(hWnd, Msg, wParam, lParam);
    }
    return 0;
}

and i have these question :
1.what is this for?

Code:

#ifdef _BORLANDC_
#pragma argsused
#endif

2.what is the meaning of this 'classname'?

Code:

const char *Clsname="Win32Test";

3.what do these codes do? set some basic attribute of the window?

Code:

WNDCLASSEX WndRegist;
        WndRegist.cbSize        = sizeof(WNDCLASSEX);
        WndRegist.style         = CS_HREDRAW | CS_VREDRAW;
        WndRegist.lpfnWndProc   = WndProcedure;
        WndRegist.cbClsExtra    = 0;
        WndRegist.cbWndExtra    = 0;
        WndRegist.hIcon         = LoadIcon(NULL, IDI_APPLICATION);
        WndRegist.hCursor       = LoadCursor(NULL, IDC_ARROW);
        WndRegist.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
        WndRegist.lpszMenuName  = NULL;
        WndRegist.lpszClassName = Clsname;
        WndRegist.hInstance     = WinIns;
        WndRegist.hIconSm       = LoadIcon(NULL, IDI_APPLICATION);
RegisterClassEx(&WndRegist);

4.does this function receive all the messages that sent by system? please tell me more details.

Code:

LRESULT CALLBACK WndProcedure(HWND hWnd, UINT Msg,WPARAM wParam, LPARAM lParam)
{
    switch(Msg)
    {
    case WM_CREATE:
        return 0;
    case WM_DESTROY:
        PostQuitMessage(WM_QUIT);
        break;
    default:
        return DefWindowProc(hWnd, Msg, wParam, lParam);
    }
    return 0;
}

any help would be great appreciated ....

thanks, it is really helpful !!!