Window Manager delete WM_WINDOW_DELETE

[perltk]

On linux, does anyone know how to intercept the window manager's delete 
call when the upper right hand "x" is pressed on the outer frame of main 
app ?
Trying to veto in the close event callback has the affect of 
disconnecting the app from the window manager resulting in an error and 
eventual termination ( takes a second or two ), but does no stop the 
delete.

perlTk has a special function something like this:
$TOP->protocol("WM_WINDOW_DELETE" => sub {.......});
Anything similiar in Wxper//WxWidgets ?

Thanks
Jeff