---
name: "xphoon"
section: "6x"
platform: "linux"
package: "xphoon"
version: "20000613-9"
release: "Debian 3.1 (Sarge)"
platforms: ["linux"]
url: "https://new.carta.tech/xphoon/6x"
---

# xphoon(6x)

displays the PHase of the mOON on the root window

## NAME

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

## SYNOPSIS

**xphoon** \[**-b**\] \[**-t** *interval* \[**-i**\]\] \[**-s**\] \[**-display** *name*\]

## DESCRIPTION

*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.

## OPTIONS

- **-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.

## NOTES

The original motivation for this program was that xsetroot was **too slow.** 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.

## SEE ALSO

*phoon*(1), [*xsetroot*(1)](/xsetroot/1.md)

## AUTHORS

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

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