If you wish to use more sophisticated editing features on Motif platforms, you can create an IDLDE macro to open a file that is currently open in the IDL Editor in another editor such as emacs or vi. Use the following procedure to create a macro:
emacs.emacs.SPAWN, 'emacs +%L %P &'
emacs in the Label field, a new "emacs" macro is added to the Macros list.SPAWN, 'xterm -e vi +%L %P &'
To use the new macros, open the desired file in the IDL editor, then select the desired Macros menu item or toolbar button.
The IDLDE always checks if the current file has been externally modified before using it. If a file was modified with an external editor, IDLDE notifies you, and asks you to reload the file before using it (you can also use the Revert to Saved option from the File menu to reload the file).