Creates a source that triggers if cancellable is cancelled and
calls its callback of type GCancellableSourceFunc This is
primarily useful for attaching to another (non-cancellable) source
with Source.addChildSource to add cancellability to it.
For convenience, you can call this with a NULLgio.Cancellable,
in which case the source will never trigger.
Creates a source that triggers if cancellable is cancelled and calls its callback of type GCancellableSourceFunc This is primarily useful for attaching to another (non-cancellable) source with Source.addChildSource to add cancellability to it.
For convenience, you can call this with a NULL gio.Cancellable, in which case the source will never trigger.
The new glib.Source will hold a reference to the gio.Cancellable