Sets a dummy callback for source. The callback will do nothing, and
if the source expects a #gboolean return value, it will return true.
(If the source expects any other type of return value, it will return
a 0/null value; whatever gobject.value.Value.init_ initializes a #GValue to for
that type.)
If the source is not one of the standard GLib types, the
closure_callback and closure_marshal fields of the #GSourceFuncs
structure must have been filled in with pointers to appropriate
functions.
Sets a dummy callback for source. The callback will do nothing, and if the source expects a #gboolean return value, it will return true. (If the source expects any other type of return value, it will return a 0/null value; whatever gobject.value.Value.init_ initializes a #GValue to for that type.)
If the source is not one of the standard GLib types, the closure_callback and closure_marshal fields of the #GSourceFuncs structure must have been filled in with pointers to appropriate functions.