1XSERVER(1)                  General Commands Manual                 XSERVER(1)
2
3
4

NAME

6       Xserver - X Window System display server
7

SYNOPSIS

9       X [option ...]
10

DESCRIPTION

12       X  is  the  generic name for the X Window System display server.  It is
13       frequently a link or a copy of the appropriate server binary for  driv‐
14       ing the most frequently used server on a given machine.
15

STARTING THE SERVER

17       The  X  server  is  usually  started from the X Display Manager program
18       xdm(1) or a similar display manager program.  This utility is run  from
19       the  system  boot  files  and takes care of keeping the server running,
20       prompting for usernames and passwords, and starting up  the  user  ses‐
21       sions.
22
23       Installations  that run more than one window system may need to use the
24       xinit(1) utility instead of a display manager.  However, xinit is to be
25       considered  a tool for building startup scripts and is not intended for
26       use by end users.  Site administrators are strongly urged to use a dis‐
27       play manager, or build other interfaces for novice users.
28
29       The  X  server  may  also  be started directly by the user, though this
30       method is usually reserved for testing and is not recommended for  nor‐
31       mal  operation.   On some platforms, the user must have special permis‐
32       sion to start the X server, often because  access  to  certain  devices
33       (e.g. /dev/mouse) is restricted.
34
35       When  the  X server starts up, it typically takes over the display.  If
36       you are running on a workstation whose console is the display, you  may
37       not be able to log into the console while the server is running.
38

OPTIONS

40       Many X servers have device-specific command line options.  See the man‐
41       ual pages for the individual  servers  for  more  details;  a  list  of
42       server-specific manual pages is provided in the SEE ALSO section below.
43
44       All  of  the X servers accept the command line options described below.
45       Some X servers may have alternative ways of  providing  the  parameters
46       described  here,  but  the values provided via the command line options
47       should override values specified via other mechanisms.
48
49       :displaynumber
50               The X server runs as the given displaynumber, which by  default
51               is  0.   If  multiple  X servers are to run simultaneously on a
52               host, each must have a unique display number.  See the  DISPLAY
53               NAMES  section  of the X(7) manual page to learn how to specify
54               which display number clients should try to use.
55
56       -a number
57               sets pointer acceleration (i.e. the ratio of how  much  is  re‐
58               ported to how much the user actually moved the pointer).
59
60       -ac     disables  host-based access control mechanisms.  Enables access
61               by any host, and permits any host to modify the access  control
62               list.   Use with extreme caution.  This option exists primarily
63               for running test suites remotely.
64
65       -audit level
66               sets the audit trail level.  The default level  is  1,  meaning
67               only  connection rejections are reported.  Level 2 additionally
68               reports all successful connections and  disconnects.   Level  4
69               enables  messages  from the SECURITY extension, if present, in‐
70               cluding generation and revocation of authorizations and  viola‐
71               tions  of  the  security  policy.   Level 0 turns off the audit
72               trail.  Audit lines are sent as standard error output.
73
74       -auth authorization-file
75               specifies a file which contains a collection  of  authorization
76               records  used  to authenticate access.  See also the xdm(1) and
77               Xsecurity(7) manual pages.
78
79       -background none
80               Asks the driver not to clear the background on startup, if  the
81               driver supports that.  May be useful for smooth transition with
82               eg. fbdev driver.  For security reasons this is not the default
83               as the screen contents might show a previous user session.
84
85       -br     sets  the  default  root  window  to solid black instead of the
86               standard root weave  pattern.    This  is  the  default  unless
87               -retro or -wr is specified.
88
89       -bs     disables backing store support on all screens.
90
91       -c      turns off key-click.
92
93       c volume
94               sets key-click volume (allowable range: 0-100).
95
96       -cc class
97               sets  the  visual  class  for the root window of color screens.
98               The class numbers are as specified  in  the  X  protocol.   Not
99               obeyed by all servers.
100
101       -core   causes the server to generate a core dump on fatal errors.
102
103       -displayfd fd
104               specifies  a  file descriptor in the launching process.  Rather
105               than specify a display number, the X  server  will  attempt  to
106               listen on successively higher display numbers, and upon finding
107               a free one, will write the display number back on this file de‐
108               scriptor as a newline-terminated string.  The -pn option is ig‐
109               nored when using -displayfd.
110
111       -deferglyphs whichfonts
112               specifies the types of fonts for which the  server  should  at‐
113               tempt  to  use  deferred  glyph loading.  whichfonts can be all
114               (all fonts), none (no fonts), or 16 (16 bit fonts only).
115
116       -dpi resolution
117               sets the resolution for all screens, in dots per inch.   To  be
118               used  when  the server cannot determine the screen size(s) from
119               the hardware.
120
121       dpms    enables DPMS (display power management  services),  where  sup‐
122               ported.   The  default state is platform and configuration spe‐
123               cific.
124
125       -dpms   disables DPMS (display power management services).  The default
126               state is platform and configuration specific.
127
128       -extensionextensionName
129               disables  named  extension.    If  an unknown extension name is
130               specified, a list of accepted extension names is printed.
131
132       +extensionextensionName
133               enables named extension.   If  an  unknown  extension  name  is
134               specified, a list of accepted extension names is printed.
135
136       -f volume
137               sets beep (bell) volume (allowable range: 0-100).
138
139       -fc cursorFont
140               sets default cursor font.
141
142       -fn font
143               sets the default font.
144
145       -fakescreenfps ps
146               sets  fake  presenter  screen  default  fps  (allowable  range:
147               1-600).
148
149       -fp fontPath
150               sets the search path for fonts.  This path is a comma separated
151               list  of directories which the X server searches for font data‐
152               bases.  See the FONTS section of this manual page for more  in‐
153               formation and the default list.
154
155       -help   prints a usage message.
156
157       -I      causes all remaining command line arguments to be ignored.
158
159       -iglx   Prohibit  creating  indirect  GLX contexts.  Indirect GLX is of
160               limited use, since it lacks support for many modern OpenGL fea‐
161               tures  and extensions; it's slower than direct contexts; and it
162               opens a large attack surface for protocol parsing errors.  This
163               is the default unless +iglx is specified.
164
165       +iglx   Allow creating indirect GLX contexts.
166
167       -maxbigreqsize size
168               sets the maximum big request to size MB.
169
170       -nocursor
171               disable the display of the pointer cursor.
172
173       -nolisten trans-type
174               disables a transport type.  For example, TCP/IP connections can
175               be disabled with -nolisten tcp.  This option may be issued mul‐
176               tiple  times to disable listening to different transport types.
177               Supported transport types are platform dependent, but  commonly
178               include:
179
180               tcp     TCP over IPv4 or IPv6
181               inet    TCP over IPv4 only
182               inet6   TCP over IPv6 only
183               unix    UNIX Domain Sockets
184               local   Platform preferred local connection method
185
186       -listen trans-type
187               enables  a transport type.  For example, TCP/IP connections can
188               be enabled with -listen tcp.  This option may be issued  multi‐
189               ple times to enable listening to different transport types.
190
191       -noreset
192               prevents  a  server  reset  when  the last client connection is
193               closed.  This overrides a previous -terminate command line  op‐
194               tion.
195
196       -p minutes
197               sets screen-saver pattern cycle time in minutes.
198
199       -pn     permits the server to continue running if it fails to establish
200               all of its well-known sockets (connection points for  clients),
201               but establishes at least one.  This option is set by default.
202
203       -nopn   causes  the  server to exit if it fails to establish all of its
204               well-known sockets (connection points for clients).
205
206       -r      turns off auto-repeat.
207
208       r       turns on auto-repeat.
209
210       -retro  starts the server with the classic stipple and cursor  visible.
211               The  default  is to start with a black root window, and to sup‐
212               press display of the cursor until the first time an application
213               calls XDefineCursor(). For kdrive servers, this implies -zap.
214
215       -s minutes
216               sets screen-saver timeout time in minutes.
217
218       -su     disables save under support on all screens.
219
220       -seat seat
221               seat to run on. Takes a string identifying a seat in a platform
222               specific syntax. On platforms which support this  feature  this
223               may  be used to limit the server to expose only a specific sub‐
224               set of devices connected to the system.
225
226       -t number
227               sets pointer acceleration threshold in pixels (i.e.  after  how
228               many pixels pointer acceleration should take effect).
229
230       -terminate
231               causes the server to terminate at server reset, instead of con‐
232               tinuing to run.  This overrides  a  previous  -noreset  command
233               line option.
234
235       -to seconds
236               sets default connection timeout in seconds.
237
238       -tst    disables  all  testing extensions (e.g., XTEST, XTrap, XTestEx‐
239               tension1, RECORD).
240
241       ttyxx   ignored, for servers started the ancient way (from init).
242
243       v       sets video-off screen-saver preference.
244
245       -v      sets video-on screen-saver preference.
246
247       -wm     forces the default backing-store of all  windows  to  be  When‐
248               Mapped.  This is a backdoor way of getting backing-store to ap‐
249               ply to all windows.  Although  all  mapped  windows  will  have
250               backing  store,  the  backing store attribute value reported by
251               the server for a window will be the last value established by a
252               client.   If it has never been set by a client, the server will
253               report the default value, NotUseful.  This behavior is required
254               by  the  X  protocol,  which  allows  the  server to exceed the
255               client's backing store expectations but does not provide a  way
256               to tell the client that it is doing so.
257
258       -wr     sets  the  default  root  window  to solid white instead of the
259               standard root weave pattern.
260
261       -x extension
262               loads the specified extension at init.  This  is  a  no-op  for
263               most implementations.
264
265       [+-]xinerama
266               enables(+)  or disables(-) the XINERAMA extension.  The default
267               state is platform and configuration specific.
268

SERVER DEPENDENT OPTIONS

270       Some X servers accept the following options:
271
272       -ld kilobytes
273               sets the data space limit of the server to the specified number
274               of  kilobytes.  A value of zero makes the data size as large as
275               possible.  The default value of -1 leaves the data space  limit
276               unchanged.
277
278       -lf files
279               sets the number-of-open-files limit of the server to the speci‐
280               fied number.  A value of zero makes the limit as large as  pos‐
281               sible.  The default value of -1 leaves the limit unchanged.
282
283       -ls kilobytes
284               sets  the stack space limit of the server to the specified num‐
285               ber of kilobytes.  A value of zero  makes  the  stack  size  as
286               large  as  possible.   The default value of -1 leaves the stack
287               space limit unchanged.
288
289       -maxclients
290               64|128|256|512 Set the maximum number  of  clients  allowed  to
291               connect to the X server.  Acceptable values are 64, 128, 256 or
292               512.
293
294       -render default|mono|gray|color sets the color allocation  policy  that
295               will be used by the render extension.
296
297               default selects  the  default  policy  defined  for the display
298                       depth of the X server.
299
300               mono    don't use any color cell.
301
302               gray    use a gray map of 13 color cells for the X  render  ex‐
303                       tension.
304
305               color   use  a  color  cube of at most 4*4*4 colors (that is 64
306                       color cells).
307
308       -dumbSched
309               disables smart scheduling on platforms that support  the  smart
310               scheduler.
311
312       -schedInterval interval
313               sets the smart scheduler's scheduling interval to interval mil‐
314               liseconds.
315

XDMCP OPTIONS

317       X servers that support XDMCP have the following  options.   See  the  X
318       Display Manager Control Protocol specification for more information.
319
320       -query hostname
321               enables  XDMCP  and  sends Query packets to the specified host‐
322               name.
323
324       -broadcast
325               enable XDMCP and broadcasts BroadcastQuery packets to the  net‐
326               work.   The first responding display manager will be chosen for
327               the session.
328
329       -multicast [address [hop count]]
330               Enable XDMCP and multicast BroadcastQuery packets to the   net‐
331               work.   The  first responding display manager is chosen for the
332               session.  If an address is specified, the multicast is sent  to
333               that  address.   If  no  address is specified, the multicast is
334               sent to the default XDMCP IPv6 multicast group.  If a hop count
335               is  specified, it is used as the maximum hop count for the mul‐
336               ticast.  If no hop count is specified, the multicast is set  to
337               a  maximum of 1 hop, to prevent the multicast from being routed
338               beyond the local network.
339
340       -indirect hostname
341               enables XDMCP and send IndirectQuery packets to  the  specified
342               hostname.
343
344       -port port-number
345               uses  the  specified  port-number for XDMCP packets, instead of
346               the default.  This option must be specified before any  -query,
347               -broadcast, -multicast, or -indirect options.
348
349       -from local-address
350               specifies the local address to connect from (useful if the con‐
351               necting host has multiple network interfaces).   The  local-ad‐
352               dress may be expressed in any form acceptable to the host plat‐
353               form's gethostbyname(3) implementation.
354
355       -once   causes the server to terminate (rather  than  reset)  when  the
356               XDMCP session ends.
357
358       -class display-class
359               XDMCP  has  an  additional  display  qualifier used in resource
360               lookup for display-specific options.   This  option  sets  that
361               value,  by  default  it is "MIT-unspecified" (not a very useful
362               value).
363
364       -cookie xdm-auth-bits
365               When testing XDM-AUTHENTICATION-1, a private key is shared  be‐
366               tween  the  server and the manager.  This option sets the value
367               of that private data (not that it is very private, being on the
368               command line!).
369
370       -displayID display-id
371               Yet  another  XDMCP specific value, this one allows the display
372               manager to identify each display so  that  it  can  locate  the
373               shared key.
374

XKEYBOARD OPTIONS

376       X  servers  that  support the XKEYBOARD (a.k.a. "XKB") extension accept
377       the following options.  All layout files specified on the command  line
378       must be located in the XKB base directory or a subdirectory, and speci‐
379       fied as the relative path from the XKB base directory.  The default XKB
380       base directory is /usr/lib/X11/xkb.
381
382       [+-]accessx [ timeout [ timeout_mask [ feedback [ options_mask ] ] ] ]
383               enables(+) or disables(-) AccessX key sequences.
384
385       -xkbdir directory
386               base  directory  for keyboard layout files.  This option is not
387               available for setuid X servers (i.e., when the X server's  real
388               and effective uids are different).
389
390       -ardelay milliseconds
391               sets  the autorepeat delay (length of time in milliseconds that
392               a key must be depressed before autorepeat starts).
393
394       -arinterval milliseconds
395               sets the autorepeat interval (length of  time  in  milliseconds
396               that should elapse between autorepeat-generated keystrokes).
397
398       -xkbmap filename
399               loads keyboard description in filename on server startup.
400

NETWORK CONNECTIONS

402       The  X server supports client connections via a platform-dependent sub‐
403       set of the following transport types: TCP/IP, Unix Domain sockets,  and
404       several  varieties  of  SVR4  local connections.  See the DISPLAY NAMES
405       section of the X(7) manual page to learn how to specify which transport
406       type clients should try to use.
407

GRANTING ACCESS

409       The  X  server  implements a platform-dependent subset of the following
410       authorization protocols: MIT-MAGIC-COOKIE-1, XDM-AUTHORIZATION-1,  XDM-
411       AUTHORIZATION-2,  SUN-DES-1,  and MIT-KERBEROS-5.  See the Xsecurity(7)
412       manual page for information on the operation of these protocols.
413
414       Authorization data required by the above protocols  is  passed  to  the
415       server  in  a  private  file  named with the -auth command line option.
416       Each time the server is about to accept the first  connection  after  a
417       reset  (or  when  the server is starting), it reads this file.  If this
418       file contains any authorization records, the local host is not automat‐
419       ically allowed access to the server, and only clients which send one of
420       the authorization records contained in the file in the connection setup
421       information  will be allowed access.  See the Xau manual page for a de‐
422       scription of the binary format of this file.  See xauth(1) for  mainte‐
423       nance of this file, and distribution of its contents to remote hosts.
424
425       The  X  server  also uses a host-based access control list for deciding
426       whether or not to accept connections from clients on a  particular  ma‐
427       chine.   If  no  other authorization mechanism is being used, this list
428       initially consists of the host on which the server is running  as  well
429       as  any  machines listed in the file /etc/Xn.hosts, where n is the dis‐
430       play number of the server.  Each line of the file should contain either
431       an  Internet hostname (e.g. expo.lcs.mit.edu) or a complete name in the
432       format family:name as described in the  xhost(1)  manual  page.   There
433       should be no leading or trailing spaces on any lines.  For example:
434
435               joesworkstation
436               corporate.company.com
437               inet:bigcpu
438               local:
439
440       Users  can add or remove hosts from this list and enable or disable ac‐
441       cess control using the xhost command  from  the  same  machine  as  the
442       server.
443
444       If  the  X  FireWall  Proxy  (xfwp) is being used without a sitepolicy,
445       host-based authorization must be turned on for clients to  be  able  to
446       connect to the X server via the xfwp.  If xfwp is run without a config‐
447       uration file and thus no sitepolicy is defined, if xfwp is using  an  X
448       server  where xhost + has been run to turn off host-based authorization
449       checks, when a client tries to connect to this X server via xfwp, the X
450       server  will  deny  the  connection.   See xfwp(1) for more information
451       about this proxy.
452
453       The X protocol intrinsically does not have any notion of window  opera‐
454       tion  permissions or place any restrictions on what a client can do; if
455       a program can connect to a display, it has full run of the  screen.   X
456       servers that support the SECURITY extension fare better because clients
457       can be designated untrusted via the authorization they use to  connect;
458       see  the xauth(1) manual page for details.  Restrictions are imposed on
459       untrusted clients that curtail the mischief they can do.  See the SECU‐
460       RITY extension specification for a complete list of these restrictions.
461
462       Sites  that  have better authentication and authorization systems might
463       wish to make use of the hooks in the libraries and the server  to  pro‐
464       vide additional security models.
465

SIGNALS

467       The X server attaches special meaning to the following signals:
468
469       SIGHUP  This  signal  causes  the  server to close all existing connec‐
470               tions, free all resources, and restore  all  defaults.   It  is
471               sent  by  the display manager whenever the main user's main ap‐
472               plication (usually an xterm or window manager) exits  to  force
473               the server to clean up and prepare for the next user.
474
475       SIGTERM This signal causes the server to exit cleanly.
476
477       SIGUSR1 This signal is used quite differently from either of the above.
478               When the server starts, it checks to see if  it  has  inherited
479               SIGUSR1 as SIG_IGN instead of the usual SIG_DFL.  In this case,
480               the server sends a SIGUSR1 to its parent process after  it  has
481               set  up  the various connection schemes.  Xdm uses this feature
482               to recognize when connecting to the server is possible.
483

FONTS

485       The X server  can  obtain  fonts  from  directories  and/or  from  font
486       servers.   The  list  of directories and font servers the X server uses
487       when trying to open a font is controlled by the font path.
488
489       The default font path is catalogue:/etc/X11/fontpath.d,built-ins .
490
491       A special kind of directory can be specified using the catalogue:  pre‐
492       fix.  Directories  specified  this way can contain symlinks pointing to
493       the real font directories. See the FONTPATH.D section for details.
494
495       The font path can be set with the -fp option or by  xset(1)  after  the
496       server has started.
497

FONTPATH.D

499       You  can  specify  a  special  kind  of  font  path  in  the form cata‐
500       logue:<dir>.  The directory specified after the catalogue: prefix  will
501       be scanned for symlinks and each symlink destination will be added as a
502       local fontfile FPE.
503
504       The symlink can be suffixed by attributes  such  as  'unscaled',  which
505       will  be passed through to the underlying fontfile FPE. The only excep‐
506       tion is the newly introduced 'pri' attribute, which will  be  used  for
507       ordering the font paths specified by the symlinks.
508
509       An example configuration:
510
511           75dpi:unscaled:pri=20 -> /usr/share/X11/fonts/75dpi
512           ghostscript:pri=60 -> /usr/share/fonts/default/ghostscript
513           misc:unscaled:pri=10 -> /usr/share/X11/fonts/misc
514           type1:pri=40 -> /usr/share/X11/fonts/Type1
515           type1:pri=50 -> /usr/share/fonts/default/Type1
516
517       This  will  add /usr/share/X11/fonts/misc as the first FPE with the at‐
518       tribute 'unscaled', second FPE will be /usr/share/X11/fonts/75dpi, also
519       with  the  attribute 'unscaled' etc. This is functionally equivalent to
520       setting the following font path:
521
522           /usr/share/X11/fonts/misc:unscaled,
523           /usr/share/X11/fonts/75dpi:unscaled,
524           /usr/share/X11/fonts/Type1,
525           /usr/share/fonts/default/Type1,
526           /usr/share/fonts/default/ghostscript
527
528

FILES

530       /etc/Xn.hosts                 Initial access control list  for  display
531                                     number n
532
533       /usr/share/fonts/X11/misc,/usr/share/fonts/X11/75dpi,/usr/share/fonts/X11/100dpi
534                                     Bitmap font directories
535
536       /usr/share/fonts/X11/TTF,/usr/share/fonts/X11/Type1
537                                     Outline font directories
538
539       /tmp/.X11-unix/Xn             Unix domain socket for display number n
540
541       /usr/adm/Xnmsgs               Error log file for display  number  n  if
542                                     run from init(8)
543
544       /usr/lib/X11/xdm/xdm-errors   Default  error  log file if the server is
545                                     run from xdm(1)
546

SEE ALSO

548       General information: X(7)
549
550       Protocols: X Window System Protocol, The X  Font  Service  Protocol,  X
551       Display Manager Control Protocol
552
553       Fonts:  bdftopcf(1), mkfontdir(1), mkfontscale(1), xfs(1), xlsfonts(1),
554       xfontsel(1), xfd(1), X Logical Font Description Conventions
555
556       Keyboards: xkeyboard-config(7)
557
558       Security: Xsecurity(7), xauth(1), Xau(1),  xdm(1),  xhost(1),  xfwp(1),
559       Security Extension Specification
560
561       Starting the server: startx(1), xdm(1), xinit(1)
562
563       Controlling  the  server  once started: xset(1), xsetroot(1), xhost(1),
564       xinput(1), xrandr(1)
565
566       Server-specific  man  pages:  Xorg(1),  Xdmx(1),  Xephyr(1),  Xnest(1),
567       Xvfb(1), Xquartz(1), XWin(1).
568
569       Server  internal documentation: Definition of the Porting Layer for the
570       X v11 Sample Server
571

AUTHORS

573       The sample server was originally written by Susan Angebranndt,  Raymond
574       Drewry,  Philip Karlton, and Todd Newman, from Digital Equipment Corpo‐
575       ration, with support from a large cast.  It has since been  extensively
576       rewritten  by  Keith Packard and Bob Scheifler, from MIT.  Dave Wiggins
577       took over post-R5 and made substantial improvements.
578
579
580
581X Version 11                  xorg-server 1.20.14                   XSERVER(1)
Impressum