based on user input scroll dynamically using Win32 functions

I am writing a sample application similar to notepad using C & Win32 functions. As soon as the user press any key on key board it displays on the output as "Key Pressed: " and then move onto the next line. When the user continues to press key he will reach to the end of the page but i m finding it difficulty in scrolling the vertical bar dynamically. I have even tried setting the scroll bar range dynamically using SetScrollInfo in WM_CHAR but still it does not work. Please suggest me a way to do this. Sample code for your reference in the attachment.

Well for starts why don't you use the standard windows EDIT control and the EM_LINESCROLL message...

The edit control should be a child of your main window sized to cover the entire client area...