What I've done is set up a wrapper to R, which is command-line driven. In addition to a few other things, I want to add the command-history method that KSH would use at the command-line with vi. So I do want it in my application and not by launching it as you suggested. The other thing I thought of was to use the examples of printing with escape characters that I saw in PortableReadKey. For instance it does : printf("\e[%d;%dH", $y, $x); To move the cursor to an absolute column and row. I figure there should be codes for inserting text rather than overwriting as it does now when I move the cursor around the command line. A couple of things like that and I won't need to call vi, but I can't find them. Thanks.