Reads from the file or communications channel in the background and posts a notification when finished.
- iOS 2.0+
- macOS 10.0+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
This method performs an asynchronous
available operation on a file or communications channel and posts an
read notification on the current thread when that operation is complete. You must call this method from a thread that has an active run loop.
The length of the data is limited to the buffer size of the underlying operating system. The notification includes a
user dictionary that contains the data read; access this object using the
Any object interested in receiving this data asynchronously must add itself as an observer of
read. In communication via stream-type sockets, the receiver is often the object returned in the
user dictionary of
Note that this method does not cause a continuous stream of notifications to be sent. If you wish to keep getting notified, you’ll also need to call
read in your observer method.