// Copyright (c) 1995, Masanao Izumo gopen(); gselect_input(ButtonPressMask | ButtonMotionMask); while(1) { switch(gpause()) { case ButtonPress: if(GEVENT_VALUE == 3) exit(0); gpset(GPOINTERX, GPOINTERY); break; case MotionNotify: gline(GPOINTERX, GPOINTERY); break; } }