xphoon - displays the PHase of the mOON on the root window

       Copyright (C) 1988, 1991 by Jef Poskanzer and Craig Leres.

       The moon-phase computation is from "moontool.c" by John Walker.

                                                  6 April 1999                                         xphoon(6)

Xphoon  sets  the  X  root  window  to  a picture of the moon in its current phase, including the partial
       lighting of the dark side by reflected earthlight.

       xphoon - displays the PHase of the mOON on the root window

       The  original  motivation  for this program was that xsetroot was tooslow.  Loading a full-screen bitmap
       took about 15 seconds.  We made a trivial program that had fullmoon.bitmap compiled in,  and  it  ran  in
       less  than  a  second.   (And incidentally, the executable was smaller than fullmoon.xbm.)  Then later we
       came up with the phase hacking, the earthlight, and the auto-scaling.

-b     Defeats the earthlight feature, forcing the dark side to be black.

       -t     Have xphoon keep running and update the picture every interval minutes.   (Normally,  xphoon  just
              sets the root picture and exits.)

       -i     Forks  a  background process and prints the process-id to stdout.  Useful if you want to make menu
              commands to refresh or kill xphoon.

       -s     Rotate the whole picture 180 degrees, resulting in a moon  picture  as  viewed  fom  the  Southern
              hemisphere.

       -demo  Demonstrate xphoon by rapidly stepping through moon phases.

phoon(1), xsetroot(1)

xphoon [-b] [-tinterval [-i]] [-s] [-displayname]