1xscreensaver(1) XScreenSaver manual xscreensaver(1)
2
6 xscreensaver - extensible screen saver and screen locking framework
7
9 xscreensaver [-display host:display.screen] [-verbose] [-no-splash]
10 [-no-capture-stderr] [-log filename]
11
13 The xscreensaver program waits until the keyboard and mouse have been
14 idle for a period, and then runs a graphics demo chosen at random. It
15 turns off as soon as there is any mouse or keyboard activity.
16 This program can lock your terminal in order to prevent others from
18 using it, though its default mode of operation is merely to display
19 pretty pictures on your screen when it is not in use.
20 It also provides configuration and control of your monitor's power-sav‐
22 ing features.
23
25 For the impatient, try this:
26 xscreensaver &
27 xscreensaver-demo
28 The xscreensaver-demo(1) program pops up a dialog box that lets you
29 configure the screen saver, and experiment with the various display
30 modes.
31 Note that xscreensaver has a client-server model: the xscreensaver pro‐
33 gram is a daemon that runs in the background; it is controlled by the
34 foreground xscreensaver-demo(1) and xscreensaver-command(1) programs.
35
37 The easiest way to configure xscreensaver is to simply run the xscreen‐
38 saver-demo(1) program, and change the settings through the GUI. The
39 rest of this manual page describes lower level ways of changing set‐
40 tings.
41 I'll repeat that because it's important:
43 The easy way to configure xscreensaver is to run the xscreensaver-
45 demo(1) program. You shouldn't need to know any of the stuff
46 described in this manual unless you are trying to do something
47 tricky, like customize xscreensaver for site-wide use or something.
48 Options to xscreensaver are stored in one of two places: in a .xscreen‐
50 saver file in your home directory; or in the X resource database. If
51 the .xscreensaver file exists, it overrides any settings in the
52 resource database.
53 The syntax of the .xscreensaver file is similar to that of the .Xde‐
55 faults file; for example, to set the timeout parameter in the .xscreen‐
56 saver file, you would write the following:
57 timeout: 5
58 whereas, in the .Xdefaults file, you would write
59 xscreensaver.timeout: 5
60 If you change a setting in the .xscreensaver file while xscreensaver is
61 already running, it will notice this, and reload the file. (The file
62 will be reloaded the next time the screen saver needs to take some
63 action, such as blanking or unblanking the screen, or picking a new
64 graphics mode.)
65 If you change a setting in your X resource database, or if you want
67 xscreensaver to notice your changes immediately instead of the next
68 time it wakes up, then you will need to reload your .Xdefaults file,
69 and then tell the running xscreensaver process to restart itself, like
70 so:
71 xrdb < ~/.Xdefaults
72 xscreensaver-command -restart
73 If you want to set the system-wide defaults, then make your edits to
74 the xscreensaver app-defaults file, which should have been installed
75 when xscreensaver itself was installed. The app-defaults file will
76 usually be named /usr/lib/X11/app-defaults/XScreenSaver, but different
77 systems might keep it in a different place (for example, /usr/open‐
78 win/lib/app-defaults/XScreenSaver on Solaris).
79 When settings are changed in the Preferences dialog box (see above) the
81 current settings will be written to the .xscreensaver file. (The .Xde‐
82 faults file and the app-defaults file will never be written by xscreen‐
83 saver itself.)
84
86 xscreensaver also accepts a few command-line options, mostly for use
87 when debugging: for normal operation, you should configure things via
88 the ~/.xscreensaver file.
89 -display host:display.screen
91 The X display to use. For displays with multiple screens,
92 XScreenSaver will manage all screens on the display simultan‐
93 iously.
94 -verbose
96 Same as setting the verbose resource to true: print diagnostics
97 on stderr and on the xscreensaver window.
98 -no-capture-stderr
100 Do not redirect the stdout and stderr streams to the xscreen‐
101 saver window itself. If xscreensaver is crashing, you might
102 need to do this in order to see the error message.
103 -log filename
105 This is exactly the same as redirecting stdout and stderr to
106 the given file (for append). This is useful when reporting
107 bugs.
108
110 When it is time to activate the screensaver, a full-screen black window
111 is created on each screen of the display. Each window is created in
112 such a way that, to any subsequently-created programs, it will appear
113 to be a "virtual root" window. Because of this, any program which
114 draws on the root window (and which understands virtual roots) can be
115 used as a screensaver. The various graphics demos are, in fact, just
116 standalone programs that know how to draw on the provided window.
117 When the user becomes active again, the screensaver windows are
119 unmapped, and the running subprocesses are killed by sending them
120 SIGTERM. This is also how the subprocesses are killed when the screen‐
121 saver decides that it's time to run a different demo: the old one is
122 killed and a new one is launched.
123 You can control a running screensaver process by using the xscreen‐
125 saver-command(1) program (which see).
126
128 Modern X servers contain support to power down the monitor after an
129 idle period. If the monitor has powered down, then xscreensaver will
130 notice this (after a few minutes), and will not waste CPU by drawing
131 graphics demos on a black screen. An attempt will also be made to
132 explicitly power the monitor back up as soon as user activity is
133 detected.
134 The ~/.xscreensaver file controls the configuration of your display's
136 power management settings: if you have used xset(1) to change your
137 power management settings, then xscreensaver will override those
138 changes with the values specified in ~/.xscreensaver (or with its
139 built-in defaults, if there is no ~/.xscreensaver file yet).
140 To change your power management settings, run xscreensaver-demo(1) and
142 change the various timeouts through the user interface. Alternatively,
143 you can edit the ~/.xscreensaver file directly.
144 If the power management section is grayed out in the xscreen‐
146 saver-demo(1) window, then that means that your X server does not sup‐
147 port the XDPMS extension, and so control over the monitor's power state
148 is not available.
149 If you're using a laptop, don't be surprised if changing the DPMS set‐
151 tings has no effect: many laptops have monitor power-saving behavior
152 built in at a very low level that is invisible to Unix and X. On such
153 systems, you can typically adjust the power-saving delays only by
154 changing settings in the BIOS in some hardware-specific way.
155 If DPMS seems not to be working with XFree86, make sure the "DPMS"
157 option is set in your /etc/X11/XF86Config file. See the XF86Config(5)
158 manual for details.
159
161 For the better part of a decade, GNOME shipped xscreensaver as-is, and
162 everything just worked out of the box. In 2005, however, they decided
163 to re-invent the wheel and ship their own replacement for the xscreen‐
164 saver daemon called "gnome-screensaver", rather than improving xscreen‐
165 saver and contributing their changes back. As a result, the "gnome-
166 screensaver" program is insecure, bug-ridden, and missing many features
167 of xscreensaver. You shouldn't use it.
168 To replace gnome-screensaver with xscreensaver:
170 1: Fully uninstall the gnome-screensaver package.
172 sudo apt-get remove gnome-screensaver
173 or possibly
174 sudo dpkg -P gnome-screensaver
175 Be careful that it doesn't try to uninstall all of GNOME.
176 2: Launch xscreensaver at login.
178 Select "Startup Applications" from the menu (or manually launch
180 "gnome-session-properties") and add "xscreensaver".
181 Do this as your normal user account, not as root. (This should
183 go without saying, because you should never, ever, ever be
184 logged in to the graphical desktop as user "root".)
185 3: Make GNOME's "Lock Screen" use xscreensaver.
187 sudo ln -sf /usr/bin/xscreensaver-command \
188 /usr/bin/gnome-screensaver-command
189 That doesn't work under Unity, though. Apparently it has its
190 own built-in screen locker which is not gnome-screensaver, and
191 cannot be removed, and yet still manages to be bug-addled and
192 insecure. Keep reinventing that wheel, guys! (If you have fig‐
193 ured out how to replace Unity's locking "feature" with xscreen‐
194 saver, let me know.)
195 4: Turn off Unity's built-in blanking.
197 Open "System Settings / Brightness & Lock";
199 Un-check "Start Automatically";
200 Set "Turn screen off when inactive for" to "Never".
201 Or possibly that has been randomly renamed again:
202 Set "Settings / Power / Power Settings" to "Never".
203 5: Log out and back in again.
205
207 Like GNOME, KDE also decided to invent their own screen saver framework
208 from scratch instead of simply using xscreensaver. To replace the KDE
209 screen saver with xscreensaver, do the following:
210 1: Turn off KDE's screen saver.
212 Open the "Control Center" and select the "Appearance & Themes /
213 Screensaver" page. Un-check "Start Automatically".
214 Or possibly: Open "System Settings" and select "Screen Locking".
216 Un-check "Lock Screen Automatically".
217 2: Find your Autostart directory.
219 Open the "System Administration / Paths" page, and see what your
220 "Autostart path" is set to: it will probably be something like
221 ~/.kde/Autostart/ or ~/.config/autostart/
222 If that doesn't work, then try this:
224 Open "System Settings / Startup/Shutdown / Autostart", and then
226 add "/usr/bin/xscreensaver".
227 If you are lucky, that will create a "xscreensaver.desktop" file
229 for you in ~/.config/autostart/ or ~/.kde/Autostart/.
230 3: Make xscreensaver be an Autostart program.
232 If it does not already exist, create a file in your autostart
233 directory called xscreensaver.desktop that contains the follow‐
234 ing six lines:
235 [Desktop Entry]
236 Exec=xscreensaver
237 Name=XScreenSaver
238 Type=Application
239 StartupNotify=false
240 X-KDE-StartupNotify=false
241 4: Make the various "lock session" buttons call xscreensaver.
243 The file you want to replace next has moved around over the
244 years. It might be called /usr/libexec/kde4/kscreenlocker, or it
245 might be called "kdesktop_lock" or "krunner_lock" or "kscreen‐
246 locker_greet", and it might be in /usr/lib/kde4/libexec/ or in
247 /usr/kde/3.5/bin/ or even in /usr/bin/, depending on the distro
248 and phase of the moon. Replace the contents of that file with
249 these two lines:
250 #!/bin/sh
251 xscreensaver-command -lock
252 Make sure the file is executable (chmod a+x).
253 Now use xscreensaver normally, controlling it via the usual xscreen‐
255 saver-demo(1) and xscreensaver-command(1) mechanisms.
256
258 If the above didn't do it, and your system has systemd(1), then give
259 this a try:
260 1: Create a service.
262 Create the file ~/.config/systemd/user/xscreensaver.service contain‐
263 ing:
264 [Unit]
265 Description=XScreenSaver
266 [Service]
267 ExecStart=/usr/bin/xscreensaver
268 Restart=always
269 [Install]
270 WantedBy=default.target
271 2. Enable it.
273 systemctl --user enable xscreensaver
274 Then restart X11.
275
277 If it's still not working, but on your distro, that newfangled sys‐
278 temd(1) nonsense has already fallen out of favor? Then maybe this will
279 work: launch the "Startup Applications" applet, click "Add", enter
280 these lines, then restart X11:
281 Name: XScreenSaver
282 Command: xscreensaver
283 Comment: xscreensaver
284
286 You can run xscreensaver from your gdm(1) session, so that the screen‐
287 saver will run even when nobody is logged in on the console. To do
288 this, run gdmconfig(1).
289 On the General page set the Local Greeter to Standard Greeter.
291 On the Background page, type the command "xscreensaver -nosplash" into
293 the Background Program field. That will cause gdm to run xscreensaver
294 while nobody is logged in, and kill it as soon as someone does log in.
295 (The user will then be responsible for starting xscreensaver on their
296 own, if they want.)
297 If that doesn't work, you can edit the config file directly. Edit
299 /etc/X11/gdm/gdm.conf to include:
300 Greeter=/usr/bin/gdmlogin
301 BackgroundProgram=xscreensaver -nosplash
302 RunBackgroundProgramAlways=true
303 In this situation, the xscreensaver process will probably be running as
304 user gdm instead of root. You can configure the settings for this
305 nobody-logged-in state (timeouts, DPMS, etc.) by editing the
306 ~gdm/.xscreensaver file.
307 It is safe to run xscreensaver as root (as xdm or gdm may do). If run
309 as root, xscreensaver changes its effective user and group ids to some‐
310 thing safe (like "nobody") before connecting to the X server or launch‐
311 ing user-specified programs.
312 An unfortunate side effect of this (important) security precaution is
314 that it may conflict with cookie-based authentication.
315 If you get "connection refused" errors when running xscreensaver from
317 gdm, then this probably means that you have xauth(1) or some other
318 security mechanism turned on. For information on the X server's access
319 control mechanisms, see the man pages for X(1), Xsecurity(1), xauth(1),
320 and xhost(1).
321
323 If you are running a system with systemd(1) 221 or newer, and if
324 xscreensaver was compiled with libsystemd support, then closing the lid
325 of your laptop will cause the screen to lock immediately.
326 If not, then the screen might not lock until a few seconds after you
328 re-open the lid. Which is less than ideal. So if you don't use systemd,
329 you might want to get in the habit of doing xscreensaver-command -lock
330 before closing the lid.
331
333 Bugs? There are no bugs. Ok, well, maybe. If you find one, please
334 let me know. https://www.jwz.org/xscreensaver/bugs.html explains how
335 to construct the most useful bug reports.
336 Locking and root logins
338 In order for it to be safe for xscreensaver to be launched by xdm,
339 certain precautions had to be taken, among them that xscreensaver
340 never runs as root. In particular, if it is launched as root (as
341 xdm is likely to do), xscreensaver will disavow its privileges, and
342 switch itself to a safe user id (such as nobody).
343 An implication of this is that if you log in as root on the con‐
345 sole, xscreensaver will refuse to lock the screen (because it can't
346 tell the difference between root being logged in on the console,
347 and a normal user being logged in on the console but xscreensaver
348 having been launched by the xdm(1) Xsetup file).
349 The solution to this is simple: you shouldn't be logging in on the
351 console as root in the first place! (What, are you crazy or some‐
352 thing?)
353 Proper Unix hygiene dictates that you should log in as yourself,
355 and su(1) to root as necessary. People who spend their day logged
356 in as root are just begging for disaster.
357 XAUTH and XDM
359 For xscreensaver to work when launched by xdm(1) or gdm(1), pro‐
360 grams running on the local machine as user "nobody" must be able to
361 connect to the X server. This means that if you want to run
362 xscreensaver on the console while nobody is logged in, you may need
363 to disable cookie-based access control (and allow all users who can
364 log in to the local machine to connect to the display).
365 You should be sure that this is an acceptable thing to do in your
367 environment before doing it. See the "Using GDM" section, above,
368 for more details.
369 Passwords
371 If you get an error message at startup like "couldn't get password
372 of user" then this probably means that you're on a system in which
373 the getpwent(3) library routine can only be effectively used by
374 root. If this is the case, then xscreensaver must be installed as
375 setuid to root in order for locking to work. Care has been taken
376 to make this a safe thing to do.
377 It also may mean that your system uses shadow passwords instead of
379 the standard getpwent(3) interface; in that case, you may need to
380 change some options with configure and recompile.
381 If you change your password after xscreensaver has been launched,
383 it will continue using your old password to unlock the screen until
384 xscreensaver is restarted. On some systems, it may accept both
385 your old and new passwords. So, after you change your password,
386 you'll have to do
387 xscreensaver-command -restart
388 to make xscreensaver notice.
389 PAM Passwords
391 If your system uses PAM (Pluggable Authentication Modules), then in
392 order for xscreensaver to use PAM properly, PAM must be told about
393 xscreensaver. The xscreensaver installation process should update
394 the PAM data (on Linux, by creating the file /etc/pam.d/xscreen‐
395 saver for you, and on Solaris, by telling you what lines to add to
396 the /etc/pam.conf file).
397 If the PAM configuration files do not know about xscreensaver, then
399 you might be in a situation where xscreensaver will refuse to ever
400 unlock the screen.
401 This is a design flaw in PAM (there is no way for a client to tell
403 the difference between PAM responding "I have never heard of your
404 module", and responding, "you typed the wrong password"). As far
405 as I can tell, there is no way for xscreensaver to automatically
406 work around this, or detect the problem in advance, so if you have
407 PAM, make sure it is configured correctly!
408 Machine Load
410 Although this program "nices" the subprocesses that it starts,
411 graphics-intensive subprograms can still overload the machine by
412 causing the X server process itself (which is not "niced") to con‐
413 sume many cycles. Care has been taken in all the modules shipped
414 with xscreensaver to sleep periodically, and not run full tilt, so
415 as not to cause appreciable load.
416 However, if you are running the OpenGL-based screen savers on a
418 machine that does not have a video card with 3D acceleration, they
419 will make your machine slow, despite nice(1).
420 Your options are: don't use the OpenGL display modes; or, collect
422 the spare change hidden under the cushions of your couch, and use
423 it to buy a video card manufactured after 1998. (It doesn't even
424 need to be fast 3D hardware: the problem will be fixed if there is
425 any 3D hardware at all.)
426 Magic Backdoor Keystrokes
428 The XFree86 X server and the Linux kernel both trap certain magic
429 keystrokes before X11 client programs ever see them. If you care
430 about keeping your screen locked, this is a big problem.
431 Ctrl+Alt+Backspace
433 This keystroke kills the X server, and on some systems, leaves
434 you at a text console. If the user launched X11 manually, that
435 text console will still be logged in. To disable this keystroke
436 globally and permanently, you need to set the DontZap flag in
437 your xorg.conf or XF86Config or XF86Config-4 file, depending
438 which is in use on your system. See XF86Config(5) for details.
439 Ctrl-Alt-F1, Ctrl-Alt-F2, etc.
441 These keystrokes will switch to a different virtual console,
442 while leaving the console that X11 is running on locked. If you
443 left a shell logged in on another virtual console, it is unpro‐
444 tected. So don't leave yourself logged in on other consoles.
445 You can disable VT switching globally and permanently by setting
446 DontVTSwitch in your xorg.conf, but that might make your system
447 harder to use, since VT switching is an actual useful feature.
448 There is no way to disable VT switching only when the screen is
450 locked. It's all or nothing.
451 Ctrl-Alt-KP_Multiply
453 This keystroke kills any X11 app that holds a lock, so typing
454 this will kill xscreensaver and unlock the screen. This so-
455 called "feature" showed up in the X server in 2008, and as of
456 2011, some vendors are shipping it turned on by default. How
457 nice. You can disable it by turning off AllowClosedownGrabs in
458 xorg.conf.
459 Alt-SysRq-F
461 This is the Linux kernel "OOM-killer" keystroke. It shoots down
462 random long-running programs of its choosing, and so might might
463 target and kill xscreensaver, and there's no way for xscreen‐
464 saver to protect itself from that. You can disable it globally
465 with:
466 echo 176 > /proc/sys/kernel/sysrq
467 There's little that I can do to make the screen locker be secure so
468 long as the kernel and X11 developers are actively working against
469 security like this. The strength of the lock on your front door
470 doesn't matter much so long as someone else in the house insists on
471 leaving a key under the welcome mat.
472 Dangerous Backdoor Server Extensions
474 Many distros enable by default several X11 server extensions that
475 can be used to bypass grabs, and thus snoop on you while you're
476 typing your password. These extensions are nominally for debugging
477 and automation, but they are also security-circumventing keystroke
478 loggers. If your server is configured to load the RECORD, XTRAP or
479 XTEST extensions, you absolutely should disable those, 100% of the
480 time. Look for them in xorg.conf or whatever it is called.
481
483 These are the X resources use by the xscreensaver program. You proba‐
484 bly won't need to change these manually (that's what the xscreen‐
485 saver-demo(1) program is for).
486 timeout (class Time)
488 The screensaver will activate (blank the screen) after the key‐
489 board and mouse have been idle for this many minutes. Default
490 10 minutes.
491 cycle (class Time)
493 After the screensaver has been running for this many minutes,
494 the currently running graphics-hack sub-process will be killed
495 (with SIGTERM), and a new one started. If this is 0, then the
496 graphics hack will never be changed: only one demo will run
497 until the screensaver is deactivated by user activity. Default
498 10 minutes.
499 The running saver will be restarted every cycle minutes even
501 when mode is one, since some savers tend to converge on a
502 steady state.
503 lock (class Boolean)
505 Enable locking: before the screensaver will turn off, it will
506 require you to type the password of the logged-in user (really,
507 the person who ran xscreensaver), or the root password. (Note:
508 this doesn't work if the screensaver is launched by xdm(1)
509 because it can't know the user-id of the logged-in user. See
510 the "Using XDM(1)" section, below.
511 lockTimeout (class Time)
513 If locking is enabled, this controls the length of the "grace
514 period" between when the screensaver activates, and when the
515 screen becomes locked. For example, if this is 5, and -timeout
516 is 10, then after 10 minutes, the screen would blank. If there
517 was user activity at 12 minutes, no password would be required
518 to un-blank the screen. But, if there was user activity at 15
519 minutes or later (that is, -lock-timeout minutes after activa‐
520 tion) then a password would be required. The default is 0,
521 meaning that if locking is enabled, then a password will be
522 required as soon as the screen blanks.
523 passwdTimeout (class Time)
525 If the screen is locked, then this is how many seconds the
526 password dialog box should be left on the screen before giving
527 up (default 30 seconds). This should not be too large: the X
528 server is grabbed for the duration that the password dialog box
529 is up (for security purposes) and leaving the server grabbed
530 for too long can cause problems.
531 dpmsEnabled (class Boolean)
533 Whether power management is enabled.
534 dpmsStandby (class Time)
536 If power management is enabled, how long until the monitor goes
537 solid black.
538 dpmsSuspend (class Time)
540 If power management is enabled, how long until the monitor goes
541 into power-saving mode.
542 dpmsOff (class Time)
544 If power management is enabled, how long until the monitor pow‐
545 ers down completely. Note that these settings will have no
546 effect unless both the X server and the display hardware sup‐
547 port power management; not all do. See the Power Management
548 section, below, for more information.
549 dpmsQuickOff (class Boolean)
551 If mode is blank and this is true, then the screen will be pow‐
552 ered down immediately upon blanking, regardless of other power-
553 management settings.
554 visualID (class VisualID)
556 This is an historical artifacts left over from when 8-bit dis‐
557 plays were still common. You should probably ignore this.
558 Specify which X visual to use by default. (Note carefully that
560 this resource is called visualID, not merely visual; if you set
561 the visual resource instead, things will malfunction in obscure
562 ways for obscure reasons.)
563 Legal values for the VisualID resource are:
565 default Use the screen's default visual (the visual of the root
567 window). This is the default.
568 best Use the visual which supports the most colors. Note,
570 however, that the visual with the most colors might be
571 a TrueColor visual, which does not support colormap
572 animation. Some programs have more interesting behav‐
573 ior when run on PseudoColor visuals than on TrueColor.
574 mono Use a monochrome visual, if there is one.
576 gray Use a grayscale or staticgray visual, if there is one
578 and it has more than one plane (that is, it's not mono‐
579 chrome).
580 color Use the best of the color visuals, if there are any.
582 GL Use the visual that is best for OpenGL programs.
584 (OpenGL programs have somewhat different requirements
585 than other X programs.)
586 class where class is one of StaticGray, StaticColor, True‐
588 Color, GrayScale, PseudoColor, or DirectColor. Selects
589 the deepest visual of the given class.
590 number where number (decimal or hex) is interpreted as a vis‐
592 ual id number, as reported by the xdpyinfo(1) program;
593 in this way you can have finer control over exactly
594 which visual gets used, for example, to select a shal‐
595 lower one than would otherwise have been chosen.
596 Note that this option specifies only the default visual that
598 will be used: the visual used may be overridden on a program-
599 by-program basis. See the description of the programs
600 resource, below.
601 installColormap (class Boolean)
603 On PseudoColor (8-bit) displays, install a private colormap
604 while the screensaver is active, so that the graphics hacks can
605 get as many colors as possible. This is the default. (This
606 only applies when the screen's default visual is being used,
607 since non-default visuals get their own colormaps automati‐
608 cally.) This can also be overridden on a per-hack basis: see
609 the discussion of the default-n name in the section about the
610 programs resource.
611 This does nothing if you have a TrueColor (16-bit or deeper)
613 display. (Which, in this century, you do.)
614 verbose (class Boolean)
616 Whether to print diagnostics. Default false.
617 timestamp (class Boolean)
619 Whether to print the time of day along with any other diagnos‐
620 tic messages. Default true.
621 splash (class Boolean)
623 Whether to display a splash screen at startup. Default true.
624 splashDuration (class Time)
626 How long the splash screen should remain visible; default 5
627 seconds.
628 helpURL (class URL)
630 The splash screen has a Help button on it. When you press it,
631 it will display the web page indicated here in your web
632 browser.
633 loadURL (class LoadURL)
635 This is the shell command used to load a URL into your web
636 browser. The default setting will load it into Mozilla/Net‐
637 scape if it is already running, otherwise, will launch a new
638 browser looking at the helpURL.
639 demoCommand (class DemoCommand)
641 This is the shell command run when the Demo button on the
642 splash window is pressed. It defaults to xscreensaver-demo(1).
643 prefsCommand (class PrefsCommand)
645 This is the shell command run when the Prefs button on the
646 splash window is pressed. It defaults to xscreen‐
647 saver-demo -prefs.
648 newLoginCommand (class NewLoginCommand)
650 If set, this is the shell command that is run when the "New
651 Login" button is pressed on the unlock dialog box, in order to
652 create a new desktop session without logging out the user who
653 has locked the screen. Typically this will be some variant of
654 gdmflexiserver(1), kdmctl(1), lxdm(1) or dm-tool(1).
655 nice (class Nice)
657 The sub-processes created by xscreensaver will be "niced" to
658 this level, so that they are given lower priority than other
659 processes on the system, and don't increase the load unneces‐
660 sarily. The default is 10. (Higher numbers mean lower prior‐
661 ity; see nice(1) for details.)
662 fade (class Boolean)
664 If this is true, then when the screensaver activates, the cur‐
665 rent contents of the screen will fade to black instead of sim‐
666 ply winking out. This only works on certain systems. A fade
667 will also be done when switching graphics hacks (when the cycle
668 timer expires). Default: true.
669 unfade (class Boolean)
671 If this is true, then when the screensaver deactivates, the
672 original contents of the screen will fade in from black instead
673 of appearing immediately. This only works on certain systems,
674 and if fade is true as well. Default false.
675 fadeSeconds (class Time)
677 If fade is true, this is how long the fade will be in seconds
678 (default 3 seconds).
679 fadeTicks (class Integer)
681 If fade is true, this is how many times a second the colormap
682 will be changed to effect a fade. Higher numbers yield
683 smoother fades, but may make the fades take longer than the
684 specified fadeSeconds if your server isn't fast enough to keep
685 up. Default 20.
686 captureStderr (class Boolean)
688 Whether xscreensaver should redirect its stdout and stderr
689 streams to the window itself. Since its nature is to take over
690 the screen, you would not normally see error messages generated
691 by xscreensaver or the sub-programs it runs; this resource will
692 cause the output of all relevant programs to be drawn on the
693 screensaver window itself, as well as being written to the con‐
694 trolling terminal of the screensaver driver process. Default
695 true.
696 ignoreUninstalledPrograms (class Boolean)
698 There may be programs in the list that are not installed on the
699 system, yet are marked as "enabled". If this preference is
700 true, then such programs will simply be ignored. If false,
701 then a warning will be printed if an attempt is made to run the
702 nonexistent program. Also, the xscreensaver-demo(1) program
703 will suppress the non-existent programs from the list if this
704 is true. Default: false.
705 authWarningSlack (class Integer)
707 If all failed unlock attempts (incorrect password entered) were
708 made within this period of time, the usual dialog that warns
709 about such attempts after a successful login will be sup‐
710 pressed. The assumption is that incorrect passwords entered
711 within a few seconds of a correct one are user error, rather
712 than hostile action. Default 20 seconds.
713 GetViewPortIsFullOfLies (class Boolean)
715 Set this to true if the xscreensaver window doesn't cover the
716 whole screen. This works around a longstanding XFree86 bug
717 #421. See the xscreensaver FAQ for details.
718 font (class Font)
720 The font used for the stdout/stderr text, if captureStderr is
721 true. Default *-medium-r-*-140-*-m-* (a 14 point fixed-width
722 font).
723 mode (class Mode)
725 Controls the behavior of xscreensaver. Legal values are:
726 random When blanking the screen, select a random display mode
728 from among those that are enabled and applicable. This
729 is the default.
730 random-same
732 Like random, but if there are multiple screens, each
733 screen will run the same random display mode, instead
734 of each screen running a different one.
735 one When blanking the screen, only ever use one particular
737 display mode (the one indicated by the selected set‐
738 ting).
739 blank When blanking the screen, just go black: don't run any
741 graphics hacks.
742 off Don't ever blank the screen, and don't ever allow the
744 monitor to power down.
745 selected (class Integer)
748 When mode is set to one, this is the one, indicated by its
749 index in the programs list. You're crazy if you count them and
750 set this number by hand: let xscreensaver-demo(1) do it for
751 you!
752 programs (class Programs)
754 The graphics hacks which xscreensaver runs when the user is
755 idle. The value of this resource is a multi-line string, one
756 sh-syntax command per line. Each line must contain exactly one
757 command: no semicolons, no ampersands.
758 When the screensaver starts up, one of these is selected
760 (according to the mode setting), and run. After the cycle
761 period expires, it is killed, and another is selected and run.
762 If a line begins with a dash (-) then that particular program
764 is disabled: it won't be selected at random (though you can
765 still select it explicitly using the xscreensaver-demo(1) pro‐
766 gram).
767 If all programs are disabled, then the screen will just be made
769 blank, as when mode is set to blank.
770 To disable a program, you must mark it as disabled with a dash
772 instead of removing it from the list. This is because the sys‐
773 tem-wide (app-defaults) and per-user (.xscreensaver) settings
774 are merged together, and if a user just deletes an entry from
775 their programs list, but that entry still exists in the system-
776 wide list, then it will come back. However, if the user dis‐
777 ables it, then their setting takes precedence.
778 If the display has multiple screens, then a different program
780 will be run for each screen. (All screens are blanked and
781 unblanked simultaneously.)
782 Note that you must escape the newlines; here is an example of
784 how you might set this in your ~/.xscreensaver file:
785 programs: \
787 qix -root \n\
788 ico -r -faces -sleep 1 -obj ico \n\
789 xdaliclock -builtin2 -root \n\
790 xv -root -rmode 5 image.gif -quit \n
791 Make sure your $PATH environment variable is set up correctly
792 before xscreensaver is launched, or it won't be able to find
793 the programs listed in the programs resource.
794 To use a program as a screensaver, two things are required:
796 that that program draw on the root window (or be able to be
797 configured to draw on the root window); and that that program
798 understand "virtual root" windows, as used by virtual window
799 managers such as tvtwm(1). (Generally, this is accomplished by
800 just including the "vroot.h" header file in the program's
801 source.)
802 Visuals:
804 Because xscreensaver was created back when dinosaurs roamed the
806 earth, it still contains support for some things you've proba‐
807 bly never seen, such as 1-bit monochrome monitors, grayscale
808 monitors, and monitors capable of displaying only 8-bit col‐
809 ormapped images.
810 If there are some programs that you want to run only when using
812 a color display, and others that you want to run only when
813 using a monochrome display, you can specify that like this:
814 mono: mono-program -root \n\
815 color: color-program -root \n\
816 More generally, you can specify the kind of visual that should
817 be used for the window on which the program will be drawing.
818 For example, if one program works best if it has a colormap,
819 but another works best if it has a 24-bit visual, both can be
820 accommodated:
821 PseudoColor: cmap-program -root \n\
822 TrueColor: 24bit-program -root \n\
823 In addition to the symbolic visual names described above (in
824 the discussion of the visualID resource) one other visual name
825 is supported in the programs list:
826 default-n
828 This is like default, but also requests the use of the
829 default colormap, instead of a private colormap. (That
830 is, it behaves as if the -no-install command-line option
831 was specified, but only for this particular hack.) This
832 is provided because some third-party programs that draw on
833 the root window (notably: xv(1), and xearth(1)) make
834 assumptions about the visual and colormap of the root win‐
835 dow: assumptions which xscreensaver can violate.
836 If you specify a particular visual for a program, and that vis‐
838 ual does not exist on the screen, then that program will not be
839 chosen to run. This means that on displays with multiple
840 screens of different depths, you can arrange for appropriate
841 hacks to be run on each. For example, if one screen is color
842 and the other is monochrome, hacks that look good in mono can
843 be run on one, and hacks that only look good in color will show
844 up on the other.
845 You shouldn't ever need to change the following resources:
847 pointerPollTime (class Time)
849 When server extensions are not in use, this controls how fre‐
850 quently xscreensaver checks to see if the mouse position or
851 buttons have changed. Default 5 seconds.
852 pointerHysteresis (class Integer)
854 If the mouse moves less than this-many pixels in a second,
855 ignore it (do not consider that to be "activity"). This is so
856 that the screen doesn't un-blank (or fail to blank) just
857 because you bumped the desk. Default: 10 pixels.
858 windowCreationTimeout (class Time)
860 When server extensions are not in use, this controls the delay
861 between when windows are created and when xscreensaver selects
862 events on them. Default 30 seconds.
863 initialDelay (class Time)
865 When server extensions are not in use, xscreensaver will wait
866 this many seconds before selecting events on existing windows,
867 under the assumption that xscreensaver is started during your
868 login procedure, and the window state may be in flux. Default
869 0. (This used to default to 30, but that was back in the days
870 when slow machines and X terminals were more common...)
871 procInterrupts (class Boolean)
873 This resource controls whether the /proc/interrupts file should
874 be consulted to decide whether the user is idle. This is the
875 default if xscreensaver has been compiled on a system which
876 supports this mechanism (i.e., Linux systems).
877 The benefit to doing this is that xscreensaver can note that
879 the user is active even when the X console is not the active
880 one: if the user is typing in another virtual console, xscreen‐
881 saver will notice that and will fail to activate. For example,
882 if you're playing Quake in VGA-mode, xscreensaver won't wake up
883 in the middle of your game and start competing for CPU.
884 The drawback to doing this is that perhaps you really do want
886 idleness on the X console to cause the X display to lock, even
887 if there is activity on other virtual consoles. If you want
888 that, then set this option to False. (Or just lock the X con‐
889 sole manually.)
890 The default value for this resource is True, on systems where
892 it works.
893 overlayStderr (class Boolean)
895 If captureStderr is True, and your server supports "overlay"
896 visuals, then the text will be written into one of the higher
897 layers instead of into the same layer as the running screen‐
898 hack. Set this to False to disable that (though you shouldn't
899 need to).
900 overlayTextForeground (class Foreground)
902 The foreground color used for the stdout/stderr text, if cap‐
903 tureStderr is true. Default: Yellow.
904 overlayTextBackground (class Background)
906 The background color used for the stdout/stderr text, if cap‐
907 tureStderr is true. Default: Black.
908 bourneShell (class BourneShell)
910 The pathname of the shell that xscreensaver uses to start sub‐
911 processes. This must be whatever your local variant of /bin/sh
912 is: in particular, it must not be csh.
913
915 DISPLAY to get the default host and display number, and to inform the
916 sub-programs of the screen on which to draw.
917 XSCREENSAVER_WINDOW
919 Passed to sub-programs to indicate the ID of the window on
920 which they should draw. This is necessary on Xinerama/RANDR
921 systems where multiple physical monitors share a single X11
922 "Screen".
923 PATH to find the sub-programs to run.
925 HOME for the directory in which to read the .xscreensaver file.
927 XENVIRONMENT
929 to get the name of a resource file that overrides the global
930 resources stored in the RESOURCE_MANAGER property.
931
933 The latest version of xscreensaver, an online version of this manual,
934 and a FAQ can always be found at https://www.jwz.org/xscreensaver/
935
937 X(1), Xsecurity(1), xauth(1), xdm(1), gdm(1), xhost(1), xscreen‐
938 saver-demo(1), xscreensaver-command(1), xscreensaver-gl-helper(1),
939 xscreensaver-getimage(1), xscreensaver-text(1).
940
942 Copyright © 1991-2020 by Jamie Zawinski. Permission to use, copy, mod‐
943 ify, distribute, and sell this software and its documentation for any
944 purpose is hereby granted without fee, provided that the above copy‐
945 right notice appear in all copies and that both that copyright notice
946 and this permission notice appear in supporting documentation. No rep‐
947 resentations are made about the suitability of this software for any
948 purpose. It is provided "as is" without express or implied warranty.
949
951 Jamie Zawinski <jwz@jwz.org>. Written in late 1991; version 1.0 posted
952 to comp.sources.x on 17-Aug-1992.
953 Please let me know if you find any bugs or make any improvements.
955 And a huge thank you to the hundreds of people who have contributed, in
957 large ways and small, to the xscreensaver collection over the past two
958 decades!
959X Version 11 5.45-1.fc33 (10-Dec-2020) xscreensaver(1)