Once you have opened an AutoLISP program file in the VLISP text editor, you can load and run it. Loading is the process by which functions in a program file are made available to the VLISP command interpreter. You can try this with the drawline.lsp sample program.
To load and run a program in a Visual LISP text editor window
VLISP responds by displaying a message in the Console window indicating it has loaded the program.
_$ (drawline)
The drawline function will ask you to specify two points, and will then draw a straight line between those points. When drawline asks for user input, VLISP turns control over to AutoCAD to prompt you for the points. What you see next depends on whether or not the AutoCAD windows are currently displayed on your desktop. If AutoCAD is already on your desktop, you'll see the AutoCAD windows. But if AutoCAD is currently minimized on your desktop, the windows won't automatically be restored and displayed. Instead, VLISP remains visible and your mouse pointer changes to a VLISP symbol.
This symbol indicates that the VLISP window is no longer active. If this is the case, you must manually switch to the AutoCAD window. Click the AutoCAD icon on the Windows task bar to activate AutoCAD.
After you respond to the prompts, control returns to VLISP and you will once again see the VLISP window.
When
you enter commands in the VLISP Console window or run a program
loaded from the text editor, you may be frequently switching back and
forth between the VLISP and AutoCAD windows. Aside from using the
standard Windows methods of switching between windows, you can activate
the AutoCAD window by choosing Window Activate AutoCAD from
the VLISP menu, or by clicking the Activate AutoCAD button on
the Run toolbar. If you are in AutoCAD and want to return to
the VLISP environment, you can enter vlisp at
the Command prompt, or choose Tools
AutoLISP
Visual
LISP Editor from the AutoCAD menu.