Asynchronously checks to see if data is available.
- iOS 2.0+
- macOS 10.0+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
The runloop modes in which the data available notification can be posted.
When the data becomes available, this method posts a
NSFile notification on the current thread. This method differs from
wait in that
modes specifies the run-loop mode (or modes) in which
NSFile can be posted.
You must call this method from a thread that has an active run loop.