Open Host Interface Objects (OHIO) is an IBM and Attachmate inspired object-oriented host access API for software implementing tn3270 and tn5250 protocols. Vendor neutral and submitted to the IETF in 1998 as an Internet standard.
OHIO address the need for a standardized advanced programming interface to the host data. OHIO does not modify the TN3270/TN5250 protocol or datastream but instead provides a common access method to that data once it arrives at the client. It uses an Object Oriented approach to divide the data into logical objects, and provides methods on those objects to allow standard access to the data.
Some OHIO's advantages are:
| • | You can run an OHIO application without having an emulation session running. |
| • | OHIO has all the benefits of the object oriented programming paradigm because it was designed as an object oriented API. |
| • | You can concentrate on the application functions, without worrying about structure packing details or parameter command codes. |
In this chapter we detail: