gcbo — Handle of the object whose callback is executing.
gcbo
gcbo is a Scilab variable automatically created
each time a callback in executed. This variable is initialised using getcallbackobject.
gcbo does not exists in Scilab environment if no
callback is currently executed.
You can use gcbo in callback functions
particularly if you write a single callback function for multiple objects,
it helps you to know which object received a user action.