X-Icon: An Icon Window Interface 1 Clinton L. Jeffery TR 91-1d Abstract This document describes the calling interface and usage conventions of X-Icon, an X Window System interface for the Icon programming language that supports high-level graphical user interface programming. It presently runs on UNIX systems under Version 11 of the X Window System. January 24, 1991; Last revised July 24, 1992 Department of Computer Science The University of Arizona Tucson, AZ 85721 1 This work was supported in part by the National Science Foundation under Grant CCR-8713690 and a grant from the AT&T Research Foundation.