NAME¶xscreensaver - extensible screen saver and screen locking framework
SYNOPSIS¶xscreensaver [-display host:display.screen] [-verbose] [-no-splash] [-no-capture-stderr] [-log filename]
DESCRIPTION¶The xscreensaver program waits until the keyboard and mouse have been idle for a period, and then runs a graphics demo chosen at random. It turns off as soon as there is any mouse or keyboard activity.
GETTING STARTED¶For the impatient, try this:
xscreensaver & xscreensaver-demoThe xscreensaver-demo(1) program pops up a dialog box that lets you configure the screen saver, and experiment with the various display modes.
CONFIGURATION¶The easiest way to configure xscreensaver is to simply run the xscreensaver-demo(1) program, and change the settings through the GUI. The rest of this manual page describes lower level ways of changing settings.
The easy way to configure xscreensaver is to run the xscreensaver-demo(1) program. You shouldn't need to know any of the stuff described in this manual unless you are trying to do something tricky, like customize xscreensaver for site-wide use or something.
timeout: 5whereas, in the .Xdefaults file, you would write
xscreensaver.timeout: 5If you change a setting in the .xscreensaver file while xscreensaver is already running, it will notice this, and reload the file. (The file will be reloaded the next time the screen saver needs to take some action, such as blanking or unblanking the screen, or picking a new graphics mode.)
xrdb < ~/.Xdefaults xscreensaver-command -restartIf you want to set the system-wide defaults, then make your edits to the xscreensaver app-defaults file, which should have been installed when xscreensaver itself was installed. The app-defaults file will usually be named /usr/lib/X11/app-defaults/XScreenSaver, but different systems might keep it in a different place (for example, /usr/openwin/lib/app-defaults/XScreenSaver on Solaris.)
COMMAND-LINE OPTIONS¶xscreensaver also accepts a few command-line options, mostly for use when debugging: for normal operation, you should configure things via the ~/.xscreensaver file.
- -display host:display.screen
- The X display to use. For displays with multiple screens, XScreenSaver will manage all screens on the display simultaniously.
- Same as setting the verbose resource to true: print diagnostics on stderr and on the xscreensaver window.
- Do not redirect the stdout and stderr streams to the xscreensaver window itself. If xscreensaver is crashing, you might need to do this in order to see the error message.
- -log filename
- This is exactly the same as redirecting stdout and stderr to the given file (for append). This is useful when reporting bugs.
HOW IT WORKS¶When it is time to activate the screensaver, a full-screen black window is created on each screen of the display. Each window is created in such a way that, to any subsequently-created programs, it will appear to be a "virtual root" window. Because of this, any program which draws on the root window (and which understands virtual roots) can be used as a screensaver. The various graphics demos are, in fact, just standalone programs that know how to draw on the provided window.
POWER MANAGEMENT¶Modern X servers contain support to power down the monitor after an idle period. If the monitor has powered down, then xscreensaver will notice this (after a few minutes), and will not waste CPU by drawing graphics demos on a black screen. An attempt will also be made to explicitly power the monitor back up as soon as user activity is detected.
USING GNOME OR UNITY¶For the better part of a decade, GNOME shipped xscreensaver as-is, and everything just worked out of the box. In 2005, however, they decided to re-invent the wheel and ship their own replacement for the xscreensaver daemon called " gnome-screensaver", rather than improving xscreensaver and contributing their changes back. As a result, the " gnome-screensaver" program is insecure, bug-ridden, and missing many features of xscreensaver. You shouldn't use it.
- 1: Fully uninstall the gnome-screensaver package.
sudo apt-get remove gnome-screensaver
- 2: Launch xscreensaver at login.
- Select "Startup Applications" from the menu (or manually launch " gnome-session-properties") and add " xscreensaver".
- 3: Make GNOME's "Lock Screen" use xscreensaver.
sudo ln -sf /usr/bin/xscreensaver-command \ /usr/bin/gnome-screensaver-commandThat doesn't work under Unity, though. Apparently it has its own built-in screen locker which is not gnome-screensaver, and cannot be removed, and yet still manages to be bug-addled and insecure. Keep reinventing that wheel, guys! (If you have figured out how to replace Unity's locking "feature" with xscreensaver, let me know.)
- 4: Turn off Unity's built-in blanking.
- Open "System Settings / Brightness &
USING KDE¶Like GNOME, KDE also decided to invent their own screen saver framework from scratch instead of simply using xscreensaver. To replace the KDE screen saver with xscreensaver, do the following:
- 1: Turn off KDE's screen saver.
- Open the "Control Center" and select the " Appearance & Themes / Screensaver" page. Un-check " Start Automatically".
- 2: Find your Autostart directory.
- Open the "System Administration / Paths" page, and see what your "Autostart path" is set to: it will probably be ~/.kde/Autostart/ or something similar.
- 3: Make xscreensaver be an Autostart program.
- Create a .desktop file in your autostart directory called
xscreensaver.desktop that contains the following five lines:
[Desktop Entry] Exec=xscreensaver Name=XScreenSaver Type=Application X-KDE-StartupNotify=false
- 4: Make the various "lock session" buttons call xscreensaver.
- The file you want to replace next has moved around over the
years. It might be called /usr/libexec/kde4/kscreenlocker, or it
might be called " kdesktop_lock" or
"krunner_lock" or "
kscreenlocker_greet", and it might be in
/usr/lib/kde4/libexec/ or in /usr/kde/3.5/bin/ or even in
/usr/bin/, depending on the distro and phase of the moon. Replace
the contents of that file with these two lines:
#!/bin/sh xscreensaver-command -lockMake sure the file is executable (chmod a+x).
USING SYSTEMD¶If the above didn't do it, and your system has systemd(1), then give this a try:
- 1: Create a service.
- Create the file
[Unit] Description=XScreenSaver [Service] ExecStart=/usr/bin/xscreensaver [Install] WantedBy=default.target2. Enable it.
systemctl --user enable xscreensaverThen restart X11.
USING UPSTART¶Still not working, but on your distro, that newfangled systemd(1) nonsense has already fallen out of favor? Then maybe this will work: launch the Startup Applications applet, click "Add", and enter these lines, then restart X11:
Name: XScreenSaver Command: xscreensaver Comment: xscreensaver
USING GDM¶You can run xscreensaver from your gdm(1) session, so that the screensaver will run even when nobody is logged in on the console. To do this, run gdmconfig(1) and on the Background page, type the command "xscreensaver -nosplash" into the Background Program field. That will cause gdm to run xscreensaver while nobody is logged in, and kill it as soon as someone does log in. (The user will then be responsible for starting xscreensaver on their own, if they want.)
BackgroundProgram=xscreensaver -nosplash RunBackgroundProgramAlways=trueIn this situation, the xscreensaver process will probably be running as user gdm instead of root. You can configure the settings for this nobody-logged-in state (timeouts, DPMS, etc.) by editing the ~gdm/.xscreensaver file.
BUGS¶Bugs? There are no bugs. Ok, well, maybe. If you find one, please let me know. https://www.jwz.org/xscreensaver/bugs.html explains how to construct the most useful bug reports.
- Locking and root logins
- In order for it to be safe for xscreensaver to be launched
by xdm, certain precautions had to be taken, among them that
xscreensaver never runs as root. In particular, if it is launched
as root (as xdm is likely to do), xscreensaver will disavow its
privileges, and switch itself to a safe user id (such as nobody.)
- XAUTH and XDM
- For xscreensaver to work when launched by xdm(1) or
gdm(1), programs running on the local machine as user
"nobody" must be able to connect to the X server. This
means that if you want to run xscreensaver on the console while nobody is
logged in, you may need to disable cookie-based access control (and allow
all users who can log in to the local machine to connect to the display.)
- If you get an error message at startup like "couldn't
get password of user" then this probably means that you're on
a system in which the getpwent(3) library routine can only be
effectively used by root. If this is the case, then xscreensaver
must be installed as setuid to root in order for locking to work. Care has
been taken to make this a safe thing to do.
xscreensaver-command -restartto make xscreensaver notice.
- PAM Passwords
- If your system uses PAM (Pluggable Authentication Modules),
then in order for xscreensaver to use PAM properly, PAM must be told about
xscreensaver. The xscreensaver installation process should update the PAM
data (on Linux, by creating the file /etc/pam.d/xscreensaver for
you, and on Solaris, by telling you what lines to add to the
- Machine Load
- Although this program "nices" the subprocesses
that it starts, graphics-intensive subprograms can still overload the
machine by causing the X server process itself (which is not
"niced") to consume many cycles. Care has been taken in all the
modules shipped with xscreensaver to sleep periodically, and not run full
tilt, so as not to cause appreciable load.
- XFree86's Magic Keystrokes
- The XFree86 X server traps certain magic keystrokes before
client programs ever see them. Two that are of note are
Ctrl+Alt+Backspace, which causes the X server to exit; and Ctrl+Alt+F
n, which switches virtual consoles. The X server will respond to
these keystrokes even if xscreensaver has the screen locked. Depending on
your setup, you might consider this a problem.
X RESOURCES¶These are the X resources use by the xscreensaver program. You probably won't need to change these manually (that's what the xscreensaver-demo(1) program is for).
- timeout (class Time)
- The screensaver will activate (blank the screen) after the keyboard and mouse have been idle for this many minutes. Default 10 minutes.
- cycle (class Time)
- After the screensaver has been running for this many
minutes, the currently running graphics-hack sub-process will be killed
(with SIGTERM), and a new one started. If this is 0, then the
graphics hack will never be changed: only one demo will run until the
screensaver is deactivated by user activity. Default 10 minutes.
- lock (class Boolean)
- Enable locking: before the screensaver will turn off, it will require you to type the password of the logged-in user (really, the person who ran xscreensaver), or the root password. ( Note: this doesn't work if the screensaver is launched by xdm(1) because it can't know the user-id of the logged-in user. See the " Using XDM(1)" section, below.
- lockTimeout (class Time)
- If locking is enabled, this controls the length of the "grace period" between when the screensaver activates, and when the screen becomes locked. For example, if this is 5, and -timeout is 10, then after 10 minutes, the screen would blank. If there was user activity at 12 minutes, no password would be required to un-blank the screen. But, if there was user activity at 15 minutes or later (that is, -lock-timeout minutes after activation) then a password would be required. The default is 0, meaning that if locking is enabled, then a password will be required as soon as the screen blanks.
- passwdTimeout (class Time)
- If the screen is locked, then this is how many seconds the password dialog box should be left on the screen before giving up (default 30 seconds.) This should not be too large: the X server is grabbed for the duration that the password dialog box is up (for security purposes) and leaving the server grabbed for too long can cause problems.
- dpmsEnabled (class Boolean)
- Whether power management is enabled.
- dpmsStandby (class Time)
- If power management is enabled, how long until the monitor goes solid black.
- dpmsSuspend (class Time)
- If power management is enabled, how long until the monitor goes into power-saving mode.
- dpmsOff (class Time)
- If power management is enabled, how long until the monitor powers down completely. Note that these settings will have no effect unless both the X server and the display hardware support power management; not all do. See the Power Management section, below, for more information.
- dpmsQuickOff (class Boolean)
- If mode is blank and this is true, then the screen will be powered down immediately upon blanking, regardless of other power-management settings.
- visualID (class VisualID)
- Specify which X visual to use by default. (Note carefully
that this resource is called visualID, not merely visual; if
you set the visual resource instead, things will malfunction in
obscure ways for obscure reasons.)
- Use the screen's default visual (the visual of the root window.) This is the default.
- Use the visual which supports the most colors. Note, however, that the visual with the most colors might be a TrueColor visual, which does not support colormap animation. Some programs have more interesting behavior when run on PseudoColor visuals than on TrueColor.
- Use a monochrome visual, if there is one.
- Use a grayscale or staticgray visual, if there is one and it has more than one plane (that is, it's not monochrome.)
- Use the best of the color visuals, if there are any.
- Use the visual that is best for OpenGL programs. (OpenGL programs have somewhat different requirements than other X programs.)
- where class is one of StaticGray, StaticColor, TrueColor, GrayScale, PseudoColor, or DirectColor. Selects the deepest visual of the given class.
- where number (decimal or hex) is interpreted as a
visual id number, as reported by the xdpyinfo(1) program; in this
way you can have finer control over exactly which visual gets used, for
example, to select a shallower one than would otherwise have been chosen.
Note that this option specifies only the default visual that will be used: the visual used may be overridden on a program-by-program basis. See the description of the programs resource, below.
- installColormap (class Boolean)
- On PseudoColor (8-bit) displays, install a private colormap
while the screensaver is active, so that the graphics hacks can get as
many colors as possible. This is the default. (This only applies when the
screen's default visual is being used, since non-default visuals get their
own colormaps automatically.) This can also be overridden on a per-hack
basis: see the discussion of the default-n name in the section
about the programs resource.
- verbose (class Boolean)
- Whether to print diagnostics. Default false.
- timestamp (class Boolean)
- Whether to print the time of day along with any other diagnostic messages. Default true.
- splash (class Boolean)
- Whether to display a splash screen at startup. Default true.
- splashDuration (class Time)
- How long the splash screen should remain visible; default 5 seconds.
- helpURL (class URL)
- The splash screen has a Help button on it. When you press it, it will display the web page indicated here in your web browser.
- loadURL (class LoadURL)
- This is the shell command used to load a URL into your web browser. The default setting will load it into Mozilla/Netscape if it is already running, otherwise, will launch a new browser looking at the helpURL.
- demoCommand (class DemoCommand)
- This is the shell command run when the Demo button on the splash window is pressed. It defaults to xscreensaver-demo(1).
- prefsCommand (class PrefsCommand)
- This is the shell command run when the Prefs button on the splash window is pressed. It defaults to xscreensaver-demo -prefs.
- newLoginCommand (class NewLoginCommand)
- If set, this is the shell command that is run when the "New Login" button is pressed on the unlock dialog box, in order to create a new desktop session without logging out the user who has locked the screen. Typically this will be some variant of gdmflexiserver(1) or kdmctl(1).
- nice (class Nice)
- The sub-processes created by xscreensaver will be "niced" to this level, so that they are given lower priority than other processes on the system, and don't increase the load unnecessarily. The default is 10. (Higher numbers mean lower priority; see nice(1) for details.)
- fade (class Boolean)
- If this is true, then when the screensaver activates, the current contents of the screen will fade to black instead of simply winking out. This only works on certain systems. A fade will also be done when switching graphics hacks (when the cycle timer expires.) Default: true.
- unfade (class Boolean)
- If this is true, then when the screensaver deactivates, the original contents of the screen will fade in from black instead of appearing immediately. This only works on certain systems, and if fade is true as well. Default false.
- fadeSeconds (class Time)
- If fade is true, this is how long the fade will be in seconds (default 3 seconds.)
- fadeTicks (class Integer)
- If fade is true, this is how many times a second the colormap will be changed to effect a fade. Higher numbers yield smoother fades, but may make the fades take longer than the specified fadeSeconds if your server isn't fast enough to keep up. Default 20.
- captureStderr (class Boolean)
- Whether xscreensaver should redirect its stdout and stderr streams to the window itself. Since its nature is to take over the screen, you would not normally see error messages generated by xscreensaver or the sub-programs it runs; this resource will cause the output of all relevant programs to be drawn on the screensaver window itself, as well as being written to the controlling terminal of the screensaver driver process. Default true.
- ignoreUninstalledPrograms (class Boolean)
- There may be programs in the list that are not installed on the system, yet are marked as "enabled." If this preference is true, then such programs will simply be ignored. If false, then a warning will be printed if an attempt is made to run the nonexistent program. Also, the xscreensaver-demo(1) program will suppress the non-existent programs from the list if this is true. Default: false.
- authWarningSlack (class Integer)
- If all failed unlock attempts (incorrect password entered) were made within this period of time, the usual dialog that warns about such attempts after a successful login will be suppressed. The assumption is that incorrect passwords entered within a few seconds of a correct one are user error, rather than hostile action. Default 20 seconds.
- GetViewPortIsFullOfLies (class Boolean)
- Set this to true if the xscreensaver window doesn't cover the whole screen. This works around a longstanding XFree86 bug #421. See the xscreensaver FAQ for details.
- font (class Font)
- The font used for the stdout/stderr text, if captureStderr is true. Default *-medium-r-*-140-*-m-* (a 14 point fixed-width font.)
- mode (class Mode)
- Controls the behavior of xscreensaver. Legal values are:
- When blanking the screen, select a random display mode from among those that are enabled and applicable. This is the default.
- Like random, but if there are multiple screens, each screen will run the same random display mode, instead of each screen running a different one.
- When blanking the screen, only ever use one particular display mode (the one indicated by the selected setting.)
- When blanking the screen, just go black: don't run any graphics hacks.
- Don't ever blank the screen, and don't ever allow the
monitor to power down.
- selected (class Integer)
- When mode is set to one, this is the one, indicated by its index in the programs list. You're crazy if you count them and set this number by hand: let xscreensaver-demo(1) do it for you!
- programs (class Programs)
- The graphics hacks which xscreensaver runs when the
user is idle. The value of this resource is a multi-line string, one
sh-syntax command per line. Each line must contain exactly one
command: no semicolons, no ampersands.
programs: \ qix -root \n\ ico -r -faces -sleep 1 -obj ico \n\ xdaliclock -builtin2 -root \n\ xv -root -rmode 5 image.gif -quit \n
Make sure your $PATH environment variable is set up correctly before xscreensaver is launched, or it won't be able to find the programs listed in the programs resource.To use a program as a screensaver, two things are required: that that program draw on the root window (or be able to be configured to draw on the root window); and that that program understand "virtual root" windows, as used by virtual window managers such as tvtwm(1). (Generally, this is accomplished by just including the "vroot.h" header file in the program's source.)Visuals:Because xscreensaver was created back when dinosaurs roamed the earth, it still contains support for some things you've probably never seen, such as 1-bit monochrome monitors, grayscale monitors, and monitors capable of displaying only 8-bit colormapped images.If there are some programs that you want to run only when using a color display, and others that you want to run only when using a monochrome display, you can specify that like this:
mono: mono-program -root \n\ color: color-program -root \n\
More generally, you can specify the kind of visual that should be used for the window on which the program will be drawing. For example, if one program works best if it has a colormap, but another works best if it has a 24-bit visual, both can be accommodated:
PseudoColor: cmap-program -root \n\ TrueColor: 24bit-program -root \n\
In addition to the symbolic visual names described above (in the discussion of the visualID resource) one other visual name is supported in the programs list:If you specify a particular visual for a program, and that visual does not exist on the screen, then that program will not be chosen to run. This means that on displays with multiple screens of different depths, you can arrange for appropriate hacks to be run on each. For example, if one screen is color and the other is monochrome, hacks that look good in mono can be run on one, and hacks that only look good in color will show up on the other.You shouldn't ever need to change the following resources:
- This is like default, but also requests the use of
the default colormap, instead of a private colormap. (That is, it behaves
as if the -no-install command-line option was specified, but only
for this particular hack.) This is provided because some third-party
programs that draw on the root window (notably: xv(1), and
xearth(1)) make assumptions about the visual and colormap of the
root window: assumptions which xscreensaver can violate.
- pointerPollTime (class Time)
- When server extensions are not in use, this controls how frequently xscreensaver checks to see if the mouse position or buttons have changed. Default 5 seconds.
- pointerHysteresis (class Integer)
- If the mouse moves less than this-many pixels in a second, ignore it (do not consider that to be "activity.") This is so that the screen doesn't un-blank (or fail to blank) just because you bumped the desk. Default: 10 pixels.
- windowCreationTimeout (class Time)
- When server extensions are not in use, this controls the delay between when windows are created and when xscreensaver selects events on them. Default 30 seconds.
- initialDelay (class Time)
- When server extensions are not in use, xscreensaver will wait this many seconds before selecting events on existing windows, under the assumption that xscreensaver is started during your login procedure, and the window state may be in flux. Default 0. (This used to default to 30, but that was back in the days when slow machines and X terminals were more common...)
- procInterrupts (class Boolean)
- This resource controls whether the /proc/interrupts
file should be consulted to decide whether the user is idle. This is the
default if xscreensaver has been compiled on a system which
supports this mechanism (i.e., Linux systems.)
- overlayStderr (class Boolean)
- If captureStderr is True, and your server supports "overlay" visuals, then the text will be written into one of the higher layers instead of into the same layer as the running screenhack. Set this to False to disable that (though you shouldn't need to.)
- overlayTextForeground (class Foreground)
- The foreground color used for the stdout/stderr text, if captureStderr is true. Default: Yellow.
- overlayTextBackground (class Background)
- The background color used for the stdout/stderr text, if captureStderr is true. Default: Black.
- bourneShell (class BourneShell)
- The pathname of the shell that xscreensaver uses to start subprocesses. This must be whatever your local variant of /bin/sh is: in particular, it must not be csh.
- to get the default host and display number, and to inform the sub-programs of the screen on which to draw.
- Passed to sub-programs to indicate the ID of the window on which they should draw. This is necessary on Xinerama/RANDR systems where multiple physical monitors share a single X11 "Screen".
- to find the sub-programs to run.
- for the directory in which to read the .xscreensaver file.
- to get the name of a resource file that overrides the global resources stored in the RESOURCE_MANAGER property.
UPGRADES¶The latest version of xscreensaver, an online version of this manual, and a FAQ can always be found at https://www.jwz.org/xscreensaver/
SEE ALSO¶X(1), Xsecurity(1), xauth(1), xdm(1), gdm(1), xhost(1), xscreensaver-demo(1), xscreensaver-command(1), xscreensaver-gl-helper(1), xscreensaver-getimage(1), xscreensaver-text(1).
COPYRIGHT¶Copyright © 1991-2015 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.
AUTHOR¶Jamie Zawinski <email@example.com>. Written in late 1991; version 1.0 posted to comp.sources.x on 17-Aug-1992.
|5.36 (10-Oct-2016)||X Version 11|