Building an APL2 X-Windows interface for VM and AIX with a general APL2-to-C interface

This paper describes APL2/X, an interface between X-Windows and APL2, designed and built at the IBM Cambridge Scientific Center. It currently runs under VM/CMS and AIX. The APL2/X VM version of the interface uses the APL2 associated processor 11 to communicate with X. The APL2/X AIX version uses a new auxiliary processor, AP144, to achieve the same functionality.APL2/X enables all of the X-Windows Xlib calls and data-structures for use from the APL2 environment. In so doing, it enables APL2 to make use of a true windowing environment. Several APL2 sample programs using the interface have been coded to illustrate and validate the interface.The basic X-Windows Xlib is actually a large application written in C. APL2/X has therefore been built upon, as well as heavily influenced, a general APL2-to-C interface that runs on various platforms: APL2 under VM/CMS and MVS/TSO, APL2 for the RISC System/6000™ under AIX, and APL2/PC under PC/DOS.