attach
Adds a struct@GLib.Source to a @context so that it will be executed within that context. Remove it by calling method@GLib.Source.destroy.
This function is safe to call from any thread, regardless of which thread the @context is running in.
Return
the ID (greater than 0) for the source within the #GMainContext.
Parameters
context
a #GMainContext (if null, the global-default main context will be used)