This is a program I've written looong time ago as one of my first experiences with X/11, testing the core functions for color and stipple. The result of this testing was an awfully written clock, modelling the arithmetic clock on the Kurfuerstendamm near Uhlandstrasse in Berlin (Germany - Europe - Northern Hemisphere - Earth - Solar System ... you know). (I don't know, wether there was another program of the same clock ever going around the net, if so, please delete & forget my version ASAP.) On color displays my first try worked fine, but the set stipple function left me with an unknown error where X normally crashed reaching the full hour. I never found out why. I never asked anybody. Within 3 years. But I took that program and erased nearly 200 lines. It isn't less ugly than before. In fact, now it works also on black and white displays through the hour, but with the prize that it redisplays the whole clock every minute. Sometimes you see the flicker, sometimes you don't. Even worse: I've managed it to delete the error for black and white displays and put in a X error for color displays. But hopefully this is also history. Because an Imakefile is obligate for a distribution, I've included it. The Makefile is the one for Sun systems. On other systems to make this clock you have to have a K&R-C-Compiler and you have to make a Makefile first (unless you like to try "gcc -o xbclock xbclock.c -lX11"), I recommend xmkmf in a proper made X distribution, so first type xmkmf and then make should work. Enjoy!