Hi again, Oberon.MarkedViewer() returns the marked viewer. It can be a Text viewer in a track or a Document viewer in a track. I can open and fill either kind of viewer but want output viewer to match input. How are these cases discriminated in code? Thanks, ... Lyall E. -- 123456789 123456789 123456789 123456789 123456789 123456789 123456789 Tel: +1 360 639 0202 Pender Is.: +1 250 629 3757 http://easthope.ca/Peter.html Bcc: peter at easthope. ca