I've written an ActiveX viewer control, similar to Adobe's PDF viewer control, for my own file format (call it ".xyz" format). So a URL like http://server/file.xyz
shows file.xyz within IE, just like the PDF viewer shows you http://server/file.pdf
What I need to do now is redirect IE commands like Print, Page Setup, Select All and Copy to my control. The PDF viewer does this - when you're looking at a PDF, File/Print launches Adobe's own Print dialog. Likewise, Edit/Select All (or Ctrl+A) selects all the text within the PDF, and Edit/Copy (or Ctrl+C) copies the selected text.
Adobe install a BHO as well as their viewer control, and I could do the same, but I can't find how to hook these commands from a BHO either.