Section: XScreenSaver manual (6)
Updated: 5.40 (12-Aug-2018)
phosphor - simulates an old terminal with long-sustain phosphor
] [-window] [-root] [-install]
] [-font font
] [-scale int
] [-delay usecs
] [-program command
[-meta] [-esc] [-bs] [-del]
program draws text on the screen in a very large
pixelated font that looks like an old low resolution dumb tty. The
pixels flare and fade out as if the phosphor was very
long-sustain. It is also a fully functional vt100 terminal emulator.
accepts the following options:
Draw on a newly-created window. This is the default.
Draw on the root window.
Install a private colormap for the window.
- -visual visual
Specify which visual to use. Legal values are the name of a visual class,
or the id number (decimal or hex) of a specific visual.
- -font font-name
The X font to use. Phosphor can take any font and scale it up to pixelate
it. The default is fixed.
- -scale int
How much to scale the font up: in other words, the size in real pixels of
the simulated pixels. Default 6.
- -ticks int
The number of colors to use when fading to black. Default 20.
- -delay usecs
The speed of the terminal: how long to wait between drawing each character.
Default 50000, or about 1/20th second.
Launch the sub-program under a PTY, so that it can address the screen
directly. This is the default.
Launch the sub-program at the end of a pipe: do not let it address the
- -program sh-command
The command to run to generate the text to display. This option may
be any string acceptable to /bin/sh. The program will be run at the
end of a pty or pipe, and any characters that it prints to stdout
will be printed on phosphor's window. The characters will be printed
artificially slowly, as per the -delay option above. If the
program exits, it will be launched again after 5 seconds.
phosphor -program 'cat /usr/src/linux*/README'
phosphor -program 'ping localhost'
phosphor -program 'ps -e'
phosphor -program 'od -txC -w6 /dev/random'
phosphor -program 'cat /dev/random'
phosphor -scale 2 -geom =1280x1024 -program 'top'
phosphor -scale 4 -geom =1280x1024 \
-program 'mtr www.kernel.org'
phosphor -program 'xemacs -nw -q -f life'
phosphor -scale 5 -geom =1280x1024 \
-program 'xemacs -nw -q --eval "(hanoi 5)"'
If you have the
text-to-speech system installed, you can have it read the screen as
phosphor prints it:
phosphor -program \
'xscreensaver-text | tee /dev/stderr | festival --tts'
You can also use phosphor as a lo-fi replacement for the
phosphor -delay 0 -program tcsh
When the user types a key with the Alt or Meta keys held down, send an
ESC character first. This is the default.
When Meta or Alt are held down, set the high bit on the character instead.
Swap Backspace and Delete. This is the default.
Do not swap Backspace and Delete.
Display the current frame rate and CPU load.
By default, phosphor
allocates a pseudo-tty for the sub-process to
run under. This has the desirable side effect that the program will be
able to use
to fetch information about terminal parameters and window size, which
many programs (such as
need to run properly. phosphor
will also set the environment
in the child process.
Any characters typed on the phosphor window will be passed along to
the sub-process. (Note that this only works when running in "window"
mode, not when running in -root mode under xscreensaver.)
to get the default host and display number.
to get the name of a resource file that overrides the global resources
stored in the RESOURCE_MANAGER property.
to inform the sub-process of the type of terminal emulation.
Copyright © 1999 by Jamie Zawinski. Permission to use, copy, modify,
distribute, and sell this software and its documentation for any purpose is
hereby granted without fee, provided that the above copyright notice appear
in all copies and that both that copyright notice and this permission notice
appear in supporting documentation. No representations are made about the
suitability of this software for any purpose. It is provided "as is" without
express or implied warranty.
Jamie Zawinski <firstname.lastname@example.org
Pty and vt100 emulation by Fredrik Tolf <email@example.com