IOHandle adds classes which represent input/output on external channels such as files or sockets. The FileStream and Socket hierarchies are modified to use IOHandle rather than to directly invoke primitives. Instances of FileStream or Socket collaborate with instances of IOHandle to separate streaming and protocol behaviors from behaviors related to external device and network access.
IOHandle has not yet been updated for Squeak 3.6 and above (changes must be applied to the new Socket hierarchy).