From c#, I want to launch a process which will open a text file in any editor and automatically move cursor to a certain line number.
I can open a file using
Perhaps you are going this the wrong way. I'm not sure what you are trying to accomplish, but I think it would be alot easier to just open the text file in an editor that belongs to your application. Perhaps another form with a WYSIWYG editor control. That way you have full control on where the cursor will land in that editor. Otherwise, there are just way too many unknowns for anything feasibly workable.