Creates a new timeout source.
The source will not initially be associated with any
and must be added to one with
g_source_attach() before it will be executed.
The scheduling granularity/accuracy of this timeout source will be in seconds.
The interval given is in terms of monotonic time, not wall clock time.
The newly-created timeout source.
|The caller of the function takes ownership of the data, and is responsible for freeing it.|