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+.\" Copyright (c) 1980, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"	This product includes software developed by the University of
+.\"	California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\"	@(#)appen.C	8.1 (Berkeley) 6/8/93
+.\"
+.ie t .oh '\*(Ln Appendix A''PS1:19-%'
+.eh 'PS1:19-%''\*(Ln Appendix A'
+.el .he ''\fIAppendix A\fR''
+.bp
+.(x
+.ti 0
+.b "Appendix A"
+.)x
+.sh 1 "Examples" 1
+.pp
+Here we present a few examples
+of how to use the package.
+They attempt to be representative,
+though not comprehensive.  Further examples can be found in the games section
+of the source tree and in various utilities that use the screen such as 
+.i systat(1) .
+.sh 2 "Screen Updating"
+.pp
+The following examples are intended to demonstrate
+the basic structure of a program
+using the screen updating sections of the package.
+Several of the programs require calculational sections
+which are irrelevant of to the example,
+and are therefore usually not included.
+It is hoped that the data structure definitions
+give enough of an idea to allow understanding
+of what the relevant portions do.
+.sh 3 "Simple Character Output"
+.pp
+This program demonstrates how to set up a window and output characters to it.
+Also, it demonstrates how one might control the output to the window.  If
+you run this program, you will get a demonstration of the character output
+chracteristics discussed in the above Character Output section.
+.(l I
+.so t2.gr
+.)l
+.sh 3 "A Small Screen Manipulator"
+.pp
+The next example follows the lines of the previous one but extends then to 
+demonstrate the various othe uses of the package.  Make sure you understand 
+how this program works as it encompasses most of anything you will
+need to do with the package.
+.(l I
+.so t3.gr
+.)l
+.sh 3 "Twinkle"
+.pp
+This is a moderately simple program which prints
+patterns on the screen.
+It switches between patterns of asterisks,
+putting them on one by one in random order,
+and then taking them off in the same fashion.
+It is more efficient to write this
+using only the motion optimization,
+as is demonstrated below.
+.(l I
+.so twinkle1.gr
+.)l
+.sh 3 "Life"
+.pp
+This program fragment models the famous computer pattern game of life
+(Scientific American, May, 1974).
+The calculational routines create a linked list of structures
+defining where each piece is.
+Nothing here claims to be optimal,
+merely demonstrative.
+This code, however,
+is a very good place to use the screen updating routines,
+as it allows them to worry about what the last position looked like,
+so you don't have to.
+It also demonstrates some of the input routines.
+.(l I
+.so life.gr
+.)l
+.sh 2 "Motion optimization"
+.pp
+The following example shows how motion optimization
+is written on its own.
+Programs which flit from one place to another without
+regard for what is already there
+usually do not need the overhead of both space and time
+associated with screen updating.
+They should instead use motion optimization.
+.sh 3 "Twinkle"
+.pp
+The
+.b twinkle
+program
+is a good candidate for simple motion optimization.
+Here is how it could be written
+(only the routines that have been changed are shown):
+.(l
+.so twinkle2.gr
+.)l