Utility method for PollableInputStream and PollableOutputStream implementations.
Creates a new SocketSource, as with
g_pollable_source_new, but also attaching child_source (with a
dummy callback), and cancellable, if they are non-null.
| pollable_stream |
the stream associated with the new source |
| child_source |
optional child source to attach |
| cancellable |
optional Cancellable to attach |
|
the new SocketSource. |