1XScreenSaver(1) General Commands Manual XScreenSaver(1)
2
6 xscreensaver - extensible screen saver and screen locking framework
7
9 xscreensaver [--display host:display.screen] [--verbose] [--version]
10 [--no-splash] [--log filename]
11
13 XScreenSaver waits until the user is idle, and then runs graphics demos
14 chosen at random. It can also lock your screen, and provides configu‐
15 ration and control of display power management.
16 XScreenSaver is also available on macOS, iOS and Android.
18
20 XScreenSaver is a daemon that runs in the background. You configure it
21 with the xscreensaver-settings(1) program.
22 xscreensaver &
24 xscreensaver-settings
25
28 When it is time to activate the screensaver, a full-screen black window
29 is created that covers each monitor. A sub-process is launched for
30 each one running a graphics demo, pointed at the appropriate window.
31 Because of this, any program which can draw on a provided window can be
32 used as a screensaver. The various graphics demos are, in fact, just
33 standalone programs that do that.
34 When the user becomes active again, the screensaver windows are un‐
36 mapped, and the running subprocesses are killed.
37 The display modes are run at a low process priority, and spend most of
39 their time sleeping/idle by default, so they should not consume signif‐
40 icant system resources.
41
43 --display host:display.screen
44 The X display to use. For displays with multiple screens,
45 XScreenSaver will manage all screens on the display simultane‐
46 ously.
47 --verbose
49 Print diagnostics to stderr.
50 --version
52 Print the version number and exit.
53 --log filename
55 Append all diagnostic output to the given file. This also im‐
56 plies --verbose. Use this when reporting bugs.
57 --no-splash
59 Don't display the splash screen at startup.
60
62 The xscreensaver-settings(1) program is where you configure if and when
63 your monitor should power off. It saves the settings in your
64 ~/.xscreensaver file. Do not use xset(1) to manually change the power
65 management settings, that won't work.
66 When the monitor is powered down, the display hacks will stop running
68 (though it may take a minute or two for XScreenSaver to notice).
69
71 If your system uses systemd(1) or elogind(8), then closing the lid of
72 your laptop will cause the screen to lock immediately.
73 If not, then the screen might not lock until a few seconds after you
75 re-open the lid. Which is less than ideal. So if you do not have sys‐
76 temd(1), you might want to get in the habit of manually locking your
77 screen before closing the lid (xscreensaver-command --lock).
78
80 Likewise, if you have systemd(1) or elogind(8), then all of the popular
81 video players and web browsers will prevent XScreenSaver from blanking
82 the screen while video is playing.
83 Both of these features require that xscreensaver-systemd(6) be able
85 connect to D-Bus.
86
88 Each desktop environment has its own system for launching long-running
89 daemons like XScreenSaver, and since many of them come bundled with
90 their own (buggy, insecure, inferior) screen-locking frameworks, it is
91 also necessary to disable those other frameworks before XScreenSaver
92 can work.
93 INSTALLING XSCREENSAVER ON GNOME OR UNITY
95 For many years, GNOME included XScreenSaver as-is, and everything just
96 worked. Not any more!
97 1: Fully uninstall the other screen saver packages:
99 sudo apt remove gnome-screensaver
101 sudo apt remove mate-screensaver
102 sudo apt remove cinnamon-screensaver
103 sudo apt remove light-locker
104 or
105 sudo rpm -e gnome-screensaver
106 sudo rpm -e mate-screensaver
107 sudo rpm -e cinnamon-screensaver
108 sudo rpm -e light-locker
109 Be careful that it doesn't try to uninstall all of GNOME.
111 2: Turn off GNOME's built-in blanking.
113 Set all of the following settings to "Never" or "Off", as these
114 are all controlled by xscreensaver-settings(1) now:
115 "Settings / Privacy / Screen Lock / Blank Screen Delay"
117 "Settings / Privacy / Screen Lock / Automatic Screen Lock"
118 "Settings / Power / Blank Screen"
119 "Settings / Power / Automatic Suspend"
120 3: Launch XScreenSaver at login.
122 Launch "Tweaks", select "Startup Applications", click the plus
123 sign, and select "XScreenSaver" (not "XScreenSaver Settings")
124 from the (very long) menu.
125 Or, see the "LAUNCHING XSCREENSAVER FROM SYSTEMD" section below.
127 That works too.
128 4: Make GNOME's "Lock" icon use XScreenSaver.
130 This used to work, but no longer does with GNOME 3.38. If you
131 figure it out, let me know! This still works for Cinnamon 4.8
132 and MATE 1.24:
133 sudo ln -sf /usr/bin/xscreensaver-command \
135 /usr/bin/gnome-screensaver-command
136 sudo ln -sf /usr/bin/xscreensaver-command \
137 /usr/bin/cinnamon-screensaver-command
138 sudo ln -sf /usr/bin/xscreensaver-command \
139 /usr/bin/mate-screensaver-command
140 sudo ln -sf /usr/bin/xscreensaver-command \
141 /usr/bin/xfce4-screensaver-command
142 sudo ln -sf /usr/bin/xscreensaver-command \
143 /usr/bin/light-locker-command
144 This change will get blown away when you upgrade.
146 INSTALLING XSCREENSAVER ON KDE
148 Like GNOME, KDE also decided to re-invent the wheel. To replace the
149 KDE screen saver with XScreenSaver, do the following:
150 1: Turn off KDE's built-in blanking.
152 In System Settings, un-check the following items, as these are
153 controlled by xscreensaver-settings(1) now:
154 "Workspace Behavior / Screen Locking / Lock automatically"
156 "Workspace Behavior / Screen Locking / After waking from sleep"
157 "Workspace Behavior / Screen Locking / Keyboard shortcut"
158 "Hardware / Power Management / Screen Energy Saving"
159 "Hardware / Power Management / Suspend session"
160 "Hardware / Power Management / Laptop lid closed" = Do Nothing
161 If there are multiple tabs, you may to change these settings on
163 all three of them: "On AC power", "Battery" and "Low Battery".
164 3: Launch XScreenSaver at login.
166 Copy the file /usr/share/applications/xscreensaver.desktop into
167 the directory ~/.config/autostart/
168 4: Make KDE's "Lock" icon use XScreenSaver.
170 Find the "kscreenlocker_greet" program. It might be in
171 "/usr/lib/*/libexec/", or it might be somewhere else. Delete
172 that file and replace it with a file containing these two lines.
173 Make it executable (chmod a+x).
174 #!/bin/sh
176 xscreensaver-command --lock &
177 This change will get blown away when you upgrade.
179 5: Turn off KDE's built-in locking on suspend, even harder.
181 Even after disabling KDE's screen locking, above, it is possible
182 that KDE will still use its built-in locker when you close your
183 laptop's lid. If that is happening, double-check the settings
184 above, but if those are correct, try the following. First, en‐
185 sure you are running KDE 5.21 or newer. Next, enable "systemd
186 user sessions" for KDE so that you can edit the parameters for
187 ksmserver:
188 kwriteconfig5 --file startkderc --group General \
190 --key systemdBoot true
191 Log out and back in.
193 Next, edit the plasma-ksmserver service to change how ksmserver
195 is launched:
196 systemctl edit --user plasma-ksmserver.service
198 Replace the contents of the file that lets you edit with this:
200 [Service]
202 ExecStart=
203 ExecStart=/usr/bin/ksmserver --no-lockscreen
204 Then log out and back in again.
206 LAUNCHING XSCREENSAVER FROM LXDE
208 Add the line @xscreensaver to /etc/xdg/lxsession/LXDE/autostart or
209 /etc/xdg/lxsession/LXDE-pi/autostart.
210 LAUNCHING XSCREENSAVER FROM SYSTEMD
212 If you are not using GNOME, KDE or LXDE, the way to launch XScreenSaver
213 at login is probably systemd(1).
214 Copy the file /usr/share/xscreensaver/xscreensaver.service into the di‐
216 rectory ~/.config/systemd/user/. Create that directory first if it
217 doesn't exist. Then enable it with:
218 systemctl --user enable xscreensaver
220 LAUNCHING XSCREENAVER FROM UPSTART
223 If you are not using GNOME, KDE or LXDE, and your system uses up‐
224 start(7) instead of systemd(1), launch the "Startup Applications" ap‐
225 plet, click "Add", and enter these lines:
226 Name: XScreenSaver
228 Command: xscreensaver
229 Comment: XScreenSaver
230 LAPTOP LIDS WITHOUT SYSTEMD
233 BSD systems or other systems without systemd(1) or elogind(8) might
234 have luck by adding "xscreensaver-command --suspend" to some appropri‐
235 ate spot in /etc/acpi/events/anything or in /etc/acpi/handler.sh, if
236 those files exist.
237 LAUNCHING XSCREENSAVER FROM GDM
239 You can run xscreensaver from your gdm(1) session, so that the screen‐
240 saver will run even when nobody is logged in on the console. To do
241 this, run gdmconfig(1).
242 On the General page set the Local Greeter to Standard Greeter.
244 On the Background page, type the command "xscreensaver --nosplash" into
246 the Background Program field. That will cause gdm to run XScreenSaver
247 while nobody is logged in, and kill it as soon as someone does log in.
248 (The user will then be responsible for starting XScreenSaver on their
249 own, if they want.)
250 If that doesn't work, you can edit the config file directly. Edit
252 /etc/X11/gdm/gdm.conf to include:
253 Greeter=/usr/bin/gdmlogin
255 BackgroundProgram=xscreensaver --nosplash
256 RunBackgroundProgramAlways=true
257 In this situation, the xscreensaver process will be running as user
259 gdm. You can configure the settings for this nobody-logged-in state
260 (timeouts, DPMS, etc.) by editing the ~gdm/.xscreensaver file.
261 If you get "connection refused" errors when running xscreensaver from
263 gdm, then this probably means that you are having xauth(1) problems.
264 For information on the X server's access control mechanisms, see the
265 man pages for X(1), Xsecurity(1), xauth(1), and xhost(1).
266 There might be a way to accomplish this with other display managers.
268 It's a mystery!
269
271 Wayland is a completely different window system that is intended to re‐
272 place X11. After 14+ years of trying, some Linux distros have finally
273 begun enabling it by default. Most deployments of it also include
274 XWayland, which is a compatibility layer that allows some X11 programs
275 to continue to work within a Wayland environment.
276 Unfortunately, XScreenSaver is not one of those programs.
278 If your system is running XWayland, XScreenSaver will malfunction in
280 two ways:
281 1: It will be unable to detect user activity in non-X11 programs.
283 This means that while a native Wayland program is selected, XScreen‐
285 Saver will think that you are idle, and may blank the screen prema‐
286 turely.
287 2: It will be unable to lock the screen.
289 This is because X11 grabs don't work properly under XWayland, so
291 there is no way for XScreenSaver to prevent the user from switching
292 away from the screen locker to another application.
293 In short, for XScreenSaver to work properly, you will need to switch
295 off Wayland and use the X Window System like in the "good old days".
296 TO DISABLE WAYLAND UNDER GNOME
298 The login screen should have a gear-icon menu that lets you change the
299 session type from "GNOME" (the Wayland session) to "GNOME on Xorg" (the
300 X11 session).
301 Alternately, edit /etc/gdm/custom.conf and make sure it includes this
303 line:
304 WaylandEnable=false
306 TO DISABLE WAYLAND UNDER KDE
308 The login screen should have a menu that lets you change the session
309 type to "Plasma (X11)".
310 Alternately, edit /etc/sddm.conf and change the SessionDir line under
312 the [Wayland] section to say:
313 SessionDir=/dev/null
315
317 XScreenSaver has a decades-long track record of securely locking your
318 screen. However, there are many things that can go wrong. X11 is a
319 very old system, and has a number of design flaws that make it suscep‐
320 tible to foot-shooting.
321 MAGIC BACKDOOR KEYSTROKES
323 The Xorg and XFree86 X servers, as well as the Linux kernel, both trap
324 certain magic keystrokes before X11 client programs ever see them. If
325 you care about keeping your screen locked, this is a big problem.
326 Ctrl+Alt+Backspace
328 This keystroke kills the X server, and on some systems, leaves you
329 at a text console. If the user launched X11 manually, that text
330 console will still be logged in. To disable this keystroke globally
331 and permanently, you need to set the DontZap flag in your
332 xorg.conf(5) or XF86Config(5) file.
333 Ctrl-Alt-F1, Ctrl-Alt-F2, etc.
335 These keystrokes will switch to a different virtual console, while
336 leaving the console that X11 is running on locked. If you left a
337 shell logged in on another virtual console, it is unprotected. So
338 don't leave yourself logged in on other consoles. You can disable
339 VT switching globally and permanently by setting DontVTSwitch in
340 your xorg.conf(5), but that might make your system harder to use,
341 since VT switching is an actual useful feature.
342 There is no way to disable VT switching only when the screen is
344 locked. It's all or nothing.
345 Ctrl-Alt-KP_Multiply
347 This keystroke kills any X11 app that holds a lock, so typing this
348 will kill XScreenSaver and unlock the screen. You can disable it by
349 turning off AllowClosedownGrabs in xorg.conf(5).
350 Alt-SysRq-F
352 This is the Linux kernel "OOM-killer" keystroke. It shoots down
353 random long-running programs of its choosing, and so might target
354 and kill XScreenSaver. You can disable this keystroke globally
355 with:
356 echo 176 > /proc/sys/kernel/sysrq
358 There's little that I can do to make the screen locker be secure so
360 long as the kernel and X11 developers are actively working against
361 security like this. The strength of the lock on your front door
362 doesn't matter much so long as someone else in the house insists on
363 leaving a key under the welcome mat.
364 THE OOM-KILLER
366 Even if you have disabled the Alt-SysRq-F OOM-killer keystroke, the
367 OOM-killer might still decide to assassinate XScreenSaver at random,
368 which will unlock your screen. If the xscreensaver-auth(6) program is
369 installed setuid, it attempts to tell the OOM-killer to leave the
370 XScreenSaver daemon alone, but that may or may not work.
371 You would think that the OOM-killer would pick the process using the
373 most memory, but most of the time it seems to pick the process that
374 would be most comically inconvenient, such as your screen locker, or
375 crond(8). You can disable the OOM-killer entirely with:
376 echo 2 > /proc/sys/vm/overcommit_memory
378 echo vm.overcommit_memory = 2 >> /etc/sysctl.conf
379 In addition to the kernel's OOM-killer, systemd(1) has its own. The
381 included xscreensaver.service file attempts to evade it, but you may
382 want to just turn it off anyway:
383 sudo systemctl disable --now systemd-oomd
385 sudo systemctl mask systemd-oomd
386 X SERVER ACCESS IS GAME OVER
389 X11's security model is all-or-nothing. If a program can connect to
390 your X server at all, either locally or over the network, it can log
391 all of your keystrokes, simulate keystrokes, launch arbitrary programs,
392 and change the settings of other programs. Assume that anything that
393 can connect to your X server can execute arbitrary code as the logged-
394 in user. See Xsecurity(1) and xauth(1).
395 PAM PASSWORDS
397 If your system uses PAM (Pluggable Authentication Modules), then PAM
398 must be configured for XScreenSaver. If it is not, then you might be
399 in a situation where you can't unlock. Probably the file you need is
400 /etc/pam.d/xscreensaver.
401 DON'T LOG IN AS ROOT
403 Never log in as root. Log in as a normal user and use sudo(1) as nec‐
404 essary. If you are logged in as root, XScreenSaver will not lock your
405 screen or run display modes, for numerous good and proper reasons.
406
408 For a single user, the proper way to configure XScreenSaver is to sim‐
409 ply run the xscreensaver-settings(1) program, and change the settings
410 through the GUI. Changes are written to the ~/.xscreensaver file.
411 If you want to set the system-wide defaults, then make your edits to
413 /etc/X11/app-defaults/XScreenSaver instead. The two files have similar
414 (but not identical) syntax.
415 You can also make changes via the X Resource Database and xrdb(1), but
417 that can be very confusing and is not really recommended.
418 Options in ~/.xscreensaver override any settings in the resource data‐
420 base or app-defaults file.
421 If you change a setting in the .xscreensaver file while XScreenSaver is
423 already running, it will notice this, and reload the file as needed.
424 But if you change a setting in the X Resource Database, you will need
425 to restart XScreenSaver for those changes to take effect:
426 xrdb < ~/.Xdefaults
428 xscreensaver-command --restart
429
432 These are the X resources use by XScreenSaver program. You probably
433 won't need to change these manually: that's what the xscreensaver-set‐
434 tings(1) program is for.
435 timeout (class Time)
437 The screensaver will activate (blank the screen) after the key‐
438 board and mouse have been idle for this many minutes. Default
439 10 minutes.
440 cycle (class Time)
442 After the screensaver has been running for this many minutes,
443 the currently running graphics-hack sub-process will be killed
444 (with SIGTERM), and a new one started. If this is 0, then the
445 graphics hack will never be changed: only one demo will run un‐
446 til the screensaver is deactivated by user activity. Default
447 10 minutes.
448 If there are multiple screens, the savers are staggered
450 slightly so that while they all change every cycle minutes,
451 they don't all change at the same time.
452 lock (class Boolean)
454 Enable locking: before the screensaver will turn off, it will
455 require you to type the password of the logged-in user.
456 lockTimeout (class Time)
458 If locking is enabled, this controls the length of the "grace
459 period" between when the screensaver activates, and when the
460 screen becomes locked. For example, if this is 5, and timeout
461 is 10, then after 10 minutes, the screen would blank. If there
462 was user activity at 12 minutes, no password would be required
463 to un-blank the screen. But, if there was user activity at 15
464 minutes or later (that is, lockTimeout minutes after activa‐
465 tion) then a password would be required. The default is 0,
466 meaning that if locking is enabled, then a password will be re‐
467 quired as soon as the screen blanks.
468 passwdTimeout (class Time)
470 If the screen is locked, then this is how many seconds the
471 password dialog box should be left on the screen before giving
472 up (default 30 seconds). A few seconds are added each time you
473 type a character.
474 dpmsEnabled (class Boolean)
476 Whether power management is enabled.
477 dpmsStandby (class Time)
479 If power management is enabled, how long until the monitor goes
480 solid black.
481 dpmsSuspend (class Time)
483 If power management is enabled, how long until the monitor goes
484 into power-saving mode.
485 dpmsOff (class Time)
487 If power management is enabled, how long until the monitor pow‐
488 ers down completely. Note that these settings will have no ef‐
489 fect unless both the X server and the display hardware support
490 power management; not all do. See the Power Management sec‐
491 tion, below, for more information.
492 dpmsQuickOff (class Boolean)
494 If mode is blank and this is true, then the screen will be pow‐
495 ered down immediately upon blanking, regardless of other power-
496 management settings.
497 verbose (class Boolean)
499 Whether to print diagnostics. Default false.
500 splash (class Boolean)
502 Whether to display a splash screen at startup. Default true.
503 splashDuration (class Time)
505 How long the splash screen should remain visible; default 5
506 seconds.
507 helpURL (class URL)
509 The splash screen has a Help button on it. When you press it,
510 it will display the web page indicated here in your web
511 browser.
512 loadURL (class LoadURL)
514 This is the shell command used to load a URL into your web
515 browser.
516 demoCommand (class DemoCommand)
518 This is the shell command run when the Demo button on the
519 splash window is pressed. It defaults to xscreensaver-set‐
520 tings(1).
521 newLoginCommand (class NewLoginCommand)
523 If set, this is the shell command that is run when the "New Lo‐
524 gin" button is pressed on the unlock dialog box, in order to
525 create a new desktop session without logging out the user who
526 has locked the screen. Typically this will be some variant of
527 gdmflexiserver(1), kdmctl(1), lxdm(1) or dm-tool(1).
528 nice (class Nice)
530 The sub-processes launched by XScreenSaver will be "niced" to
531 this level, so that they are given lower priority than other
532 processes on the system, and don't increase the load unneces‐
533 sarily. The default is 10. (Higher numbers mean lower prior‐
534 ity; see nice(1) for details.)
535 fade (class Boolean)
537 If this is true, then when the screensaver activates, the desk‐
538 top will fade to black instead of simply winking out. Default:
539 true.
540 unfade (class Boolean)
542 If this is true, then when the screensaver deactivates, desktop
543 will fade back ininstead of appearing immediately. This is
544 only done if fade is true as well. Default: true.
545 fadeSeconds (class Time)
547 If fade is true, this is how long the fade will be in seconds.
548 Default 3 seconds.
549 ignoreUninstalledPrograms (class Boolean)
551 There may be programs in the list that are not installed on the
552 system, yet are marked as "enabled". If this preference is
553 true, then such programs will simply be ignored. If false,
554 then a warning will be printed if an attempt is made to run the
555 nonexistent program. Also, the xscreensaver-settings(1) pro‐
556 gram will suppress the non-existent programs from the list if
557 this is true. Default: false.
558 authWarningSlack (class Integer)
560 After you successfully unlock the screen, a dialog may pop up
561 informing you of previous failed login attempts. If all of
562 those login attemps were within this amount of time, they are
563 ignored. The assumption is that incorrect passwords entered
564 within a few seconds of a correct one are user error, rather
565 than hostile action. Default 20 seconds.
566 mode (class Mode)
568 Controls the screen-saving behavior. Valid values are:
569 random When blanking the screen, select a random display mode
571 from among those that are enabled and applicable. This
572 is the default.
573 random-same
575 Like random, but if there are multiple screens, each
576 screen will run the same random display mode, instead
577 of each screen running a different one.
578 one When blanking the screen, only ever use one particular
580 display mode (the one indicated by the selected set‐
581 ting).
582 blank When blanking the screen, just go black: don't run any
584 graphics hacks.
585 off Don't ever blank the screen, and don't ever allow the
587 monitor to power down.
588 selected (class Integer)
590 When mode is set to one, this is the one, indicated by its in‐
591 dex in the programs list. You're crazy if you count them and
592 set this number by hand: let xscreensaver-settings(1) do it for
593 you!
594 programs (class Programs)
596 The graphics hacks which XScreenSaver runs when the user is
597 idle. The value of this resource is a multi-line string, one
598 sh-syntax command per line. Each line must contain exactly one
599 command: no semicolons, no ampersands.
600 When the screensaver starts up, one of these is selected (ac‐
602 cording to the mode setting), and run. After the cycle period
603 expires, it is killed, and another is selected and run.
604 If a line begins with a dash (-) then that particular program
606 is disabled: it won't be selected at random (though you can
607 still select it explicitly using the xscreensaver-settings(1)
608 program).
609 If all programs are disabled, then the screen will just be made
611 blank, as when mode is set to blank.
612 To disable a program, you must mark it as disabled with a dash
614 instead of removing it from the list. This is because the sys‐
615 tem-wide (app-defaults) and per-user (.xscreensaver) settings
616 are merged together, and if a user just deletes an entry from
617 their programs list, but that entry still exists in the system-
618 wide list, then it will come back. However, if the user dis‐
619 ables it, then their setting takes precedence.
620 The default XScreenSaver hacks directory (typically
622 /usr/libexec/xscreensaver/) is prepended to $PATH before
623 searching for these programs.
624 To use a program as a screensaver, it must be able to render
626 onto the window provided to it in the $XSCREENSAVER_WINDOW en‐
627 vironment variable. If it creates and maps its own window in‐
628 stead, it won't work. It must render onto the provided window.
629 Visuals:
630 Because XScreenSaver was created back when dinosaurs roamed the
632 earth, it still contains support for some things you've proba‐
633 bly never seen, such as 1-bit monochrome monitors, grayscale
634 monitors, and monitors capable of displaying only 8-bit col‐
635 ormapped images.
636 If there are some programs that you want to run only when using
638 a color display, and others that you want to run only when us‐
639 ing a monochrome display, you can specify that like this:
640 mono: mono-program -root \n\
642 color: color-program -root \n\
643 More generally, you can specify the kind of visual that should
645 be used for the window on which the program will be drawing.
646 For example, if one program works best if it has a colormap,
647 but another works best if it has a 24-bit visual, both can be
648 accommodated:
649 PseudoColor: cmap-program -root \n\
651 TrueColor: 24bit-program -root \n\
652 In addition to the symbolic visual names described above (in
654 the discussion of the visualID resource) one other visual name
655 is supported in the programs list:
656 default-n
658 This is like default, but also requests the use of the default
659 colormap, instead of a private colormap.
660 If you specify a particular visual for a program, and that visual does
662 not exist on the screen, then that program will not be chosen to run.
663 This means that on displays with multiple screens of different depths,
664 you can arrange for appropriate hacks to be run on each. For example,
665 if one screen is color and the other is monochrome, hacks that look
666 good in mono can be run on one, and hacks that only look good in color
667 will show up on the other.
668 visualID (class VisualID)
670 This is an historical artifact left over from when 8-bit dis‐
671 plays were still common. You should probably ignore this.
672 Specify which X visual to use by default. (Note carefully that
674 this resource is called visualID, not merely visual; if you set
675 the visual resource instead, things will malfunction in obscure
676 ways for obscure reasons.)
677 Valid values for the VisualID resource are:
679 default Use the screen's default visual (the visual of the root
681 window). This is the default.
682 best Use the visual which supports the most colors. Note,
684 however, that the visual with the most colors might be
685 a TrueColor visual, which does not support colormap an‐
686 imation. Some programs have more interesting behavior
687 when run on PseudoColor visuals than on TrueColor.
688 mono Use a monochrome visual, if there is one.
690 gray Use a grayscale or staticgray visual, if there is one
692 and it has more than one plane (that is, it's not mono‐
693 chrome).
694 color Use the best of the color visuals, if there are any.
696 GL Use the visual that is best for OpenGL programs.
698 (OpenGL programs have somewhat different requirements
699 than other X programs.)
700 class where class is one of StaticGray, StaticColor, True‐
702 Color, GrayScale, PseudoColor, or DirectColor. Selects
703 the deepest visual of the given class.
704 N where number (decimal or hex) is interpreted as a vis‐
706 ual id number, as reported by the xdpyinfo(1) program;
707 in this way you can have finer control over exactly
708 which visual gets used, for example, to select a shal‐
709 lower one than would otherwise have been chosen.
710 Note that this option specifies only the default visual that
712 will be used: the visual used may be overridden on a program-
713 by-program basis. See the description of the programs re‐
714 source, above.
715 installColormap (class Boolean)
717 This is an historical artifact left over from when 8-bit dis‐
718 plays were still common. On PseudoColor (8-bit) displays, in‐
719 stall a private colormap while the screensaver is active, so
720 that the graphics hacks can get as many colors as possible.
721 This is the default. (This only applies when the screen's de‐
722 fault visual is being used, since non-default visuals get their
723 own colormaps automatically.) This can also be overridden on a
724 per-hack basis: see the discussion of the default-n name in the
725 section about the programs resource.
726 This does nothing if you have a TrueColor (16-bit or deeper)
728 display. (Which, in this century, you do.)
729 pointerHysteresis (class Integer)
731 If the mouse moves less than this-many pixels in a second, ig‐
732 nore it (do not consider that to be "activity"). This is so
733 that the screen doesn't un-blank (or fail to blank) just be‐
734 cause you bumped the desk. Default: 10 pixels.
735 A single pixel of motion will still cause the monitor to power
737 back on, but not un-blank. This is because the X11 server it‐
738 self unfortunately handles power-management-related activity
739 detection rather than XScreenSaver.
740
742 https://www.jwz.org/xscreensaver/bugs.html explains how to write the
743 most useful bug reports. If you find a bug, please let me know!
744
746 DISPLAY to get the default host and display number, and to inform the
747 sub-programs of the screen on which to draw.
748 XSCREENSAVER_WINDOW
750 Passed to sub-programs to indicate the ID of the window on
751 which they should draw.
752 PATH to find the sub-programs to run, including the display modes.
754 HOME for the directory in which to read the .xscreensaver file.
756 XENVIRONMENT
758 to get the name of a resource file that overrides the global
759 resources stored in the RESOURCE_MANAGER property.
760
762 The latest version of XScreenSaver, an online version of this manual,
763 and a FAQ can always be found at https://www.jwz.org/xscreensaver/
764
766 X(1), Xsecurity(1), xauth(1), xdm(1), gdm(1), xhost(1), systemd(1), el‐
767 ogind(8), xscreensaver-settings(1), xscreensaver-command(1), xscreen‐
768 saver-systemd(6), xscreensaver-gl-helper(6), xscreensaver-getimage(6),
769 xscreensaver-text(6).
770
772 Copyright © 1991-2022 by Jamie Zawinski. Permission to use, copy, mod‐
773 ify, distribute, and sell this software and its documentation for any
774 purpose is hereby granted without fee, provided that the above copy‐
775 right notice appear in all copies and that both that copyright notice
776 and this permission notice appear in supporting documentation. No rep‐
777 resentations are made about the suitability of this software for any
778 purpose. It is provided "as is" without express or implied warranty.
779
781 Jamie Zawinski <jwz@jwz.org>
782 Please let me know if you find any bugs or make any improvements.
784 And a huge thank you to the hundreds of people who have contributed, in
786 large ways and small, to the XScreenSaver collection over the past
787 three decades!
788X Version 11 6.06-1.fc37 (12-Dec-2022) XScreenSaver(1)