The win32 API implements a simple message window example

#include<windows.h>
LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);
int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,PSTR szCmdLine,int iCmdShow)
{
static TCHAR szAppName[]=TEXT("HelloWin");
HWND hwnd;
MSG msg;
WNDCLASS wndclass;
wndclass.style                =CS_HREDRAW|CS_VREDRAW;
wndclass.lpfnWndProc          =WndProc;
wndclass.cbClsExtra           =0;
wndclass.cbWndExtra           =0;
wndclass.hInstance            =hInstance;
wndclass.hIcon                =LoadIcon(NULL,IDI_APPLICATION);
wndclass.hCursor              =LoadCursor(NULL,IDC_ARROW);
wndclass.hbrBackground        =(HBRUSH)GetStockObject(WHITE_BRUSH);
wndclass.lpszMenuName         =NULL;
wndclass.lpszClassName        =szAppName;
if(!RegisterClass(&wndclass))
{
   MessageBox(NULL,TEXT("This program requires Windows NT!"),szAppName,MB_ICONERROR);
   return 0;
}
hwnd=CreateWindow(szAppName,TEXT("The hello program"),WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,
      CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,hInstance,NULL);
ShowWindow(hwnd,iCmdShow);
UpdateWindow(hwnd);
while(GetMessage(&msg,NULL,0,0))
{
    TranslateMessage(&msg);
 DispatchMessage(&msg);
}
return msg.wParam;
}
LRESULT CALLBACK WndProc(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam)
{
HDC            hdc;
PAINTSTRUCT    ps;
RECT           rect;
switch(message)
{
case WM_CREATE:
 PlaySound(TEXT("hellowin.wav"),NULL,SND_FILENAME|SND_ASYNC);
 return 0;
case WM_PAINT:
 hdc=BeginPaint(hwnd,&ps);
 GetClientRect(hwnd,&rect);
 DrawText(hdc,TEXT("HELLO WORLD!"),-1,&rect,
       DT_SINGLELINE|DT_CENTER|DT_VCENTER);
 EndPaint(hwnd,&ps);
 return 0;
case WM_DESTROY:
 PostQuitMessage(0);
 return 0;
}
return DefWindowProc(hwnd,message,wParam,lParam);
}