add_child_source

Adds child_source to this as a "polled" source; when this is added to a MainContext, child_source will be automatically added with the same priority, when child_source is triggered, it will cause this to dispatch (in addition to calling its own callback), and when this is destroyed, it will destroy child_source as well.

(this will also still be dispatched if its own prepare/check functions indicate that it is ready.)

If you don't need child_source to do anything on its own when it triggers, you can call source_set_dummy_callback on it to set a callback that does nothing (except return true if appropriate).

this will hold a reference on child_source while child_source is attached to it.

This API is only intended to be used by implementations of SignalSource. Do not call this API on a SignalSource that you did not create.

Parameters: