COPY, CUT, PASTE
These three call-back functions transfer information between the edit box (%eb,
%rd, %rf, %fs, or %re) that has the focus and the clipboard. Typically, they
are used as the call-back function for an edit-copy/cut/paste menu item. These
call-back functions require no additional winio@ arguments.
Menu items and buttons attached to these callback functions are greyed according
to circumstances. For example, a control associated with the CUT function would
be greyed if no text were currently marked as selected on the screen. However,
if the control has a grey control variable then this variable takes precedence.
Apart from %eb, standard accelerator keys (Ctrl+C, Ctrl+X, and Ctrl+V) can also
be used for COPY, CUT and PASTE.