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X(7)		       Miscellaneous Information Manual			  X(7)

       X - a portable, network-transparent window system

       The  X  Window System is	a network transparent window system which runs
       on a wide range of computing and	graphics machines.  It should be rela-
       tively straightforward to build the X.Org Foundation software distribu-
       tion on most ANSI C and POSIX compliant systems.	 Commercial  implemen-
       tations are also	available for a	wide range of platforms.

       The X.Org Foundation requests that the following	names be used when re-
       ferring to this software:

				   X Window System
				    X Version 11
			     X Window System, Version 11

       X Window	System is a trademark of The Open Group.

       X Window	System servers run on computers	 with  bitmap  displays.   The
       server distributes user input to	and accepts output requests from vari-
       ous client programs through a variety of	different interprocess	commu-
       nication	 channels.   Although  the  most common	case is	for the	client
       programs	to be running on the same machine as the server,  clients  can
       be  run transparently from other	machines (including machines with dif-
       ferent architectures and	operating systems) as well.

       X supports overlapping hierarchical subwindows and  text	 and  graphics
       operations, on both monochrome and color	displays.  For a full explana-
       tion of the functions that are available, see the Xlib -	C  Language  X
       Interface  manual,  the	X  Window System Protocol specification, the X
       Toolkit Intrinsics - C Language Interface manual, and  various  toolkit
       documents.   Those manuals, specifications, & documents may be found in
       /usr/local/share/doc  or	  on   the   X.Org   Foundation	  website   at

       The number of programs that use X is quite large.  Sample programs pro-
       vided by	the X.Org Foundation include: a	terminal  emulator,  xterm;  a
       window  manager,	 twm;  a compositing manager, xcompmgr;	a display man-
       ager, xdm; a console redirect program, xconsole;	utilities for managing
       input and output	devices, xinput	and xrandr; resource listing/manipula-
       tion tools, appres, editres; access control programs, xauth, xhost, and
       iceauth;	 user  preference  setting  programs,  transset, xrdb, xcmsdb,
       xset, xsetroot, xstdcmap, and xmodmap; clocks, xclock and oclock;  font
       display	utilities, xfd and xfontsel; utilities for listing information
       about displays, extensions, and resources, xdpyinfo, xdriinfo,  xvinfo,
       xwininfo, xlsclients, xprop, xlsatoms, xlsclients, and xlsfonts;	screen
       image manipulation utilities, xwd, xwud,	and xmag; a  performance  mea-
       surement	utility, x11perf; a font compiler, bdftopcf; a font server and
       related utilities, xfs, xfsinfo,	fslsfonts, fstobdf; a  display	server
       and  related  utilities,	 Xserver, rgb, mkfontdir; a clipboard manager,
       xclipboard; keyboard description	compiler and related  utilities,  xkb-
       comp,  setxkbmap	 xkbprint,  xkbbell, xkbevd, xkbvleds, and xkbwatch; a
       utility to terminate clients, xkill; and	a utility to cause part	or all
       of the screen to	be redrawn, xrefresh.

       Many  other  utilities,	window managers, games,	toolkits, etc. are in-
       cluded as packages in  many  operating  system  distributions,  or  are
       available on the	Internet.  See your site administrator or distro pack-
       age manager for details.

       There are two main ways of getting the X	server and an initial  set  of
       client  applications  started.	The  particular	method used depends on
       what operating system you are running and whether or not	you use	 other
       window systems in addition to X.

       Display Manager
	       If you want to always have X running on your display, your site
	       administrator can set your machine up to	use a Display  Manager
	       such as xdm, gdm, or kdm.  This program is typically started by
	       the system at boot time and takes care of  keeping  the	server
	       running and getting users logged	in.  If	you are	running	one of
	       these display managers, you will	normally see a window  on  the
	       screen  welcoming  you  to the system and asking	for your login
	       information.  Simply type them in as you	would at a normal ter-
	       minal.  If you make a mistake, the display manager will display
	       an error	message	and ask	you to try again.  After you have suc-
	       cessfully  logged  in, the display manager will start up	your X
	       environment.  The documentation for the display manager you use
	       can provide more	details.

       xinit (run manually from	the shell)
	       Sites  that support more	than one window	system might choose to
	       use the xinit program for starting X manually.  If this is true
	       for  your  machine,  your site administrator will probably have
	       provided	a program named	"x11", "startx", or "xstart" that will
	       do site-specific	initialization (such as	loading	convenient de-
	       fault resources,	running	a window manager, displaying a	clock,
	       and  starting  several  terminal	 emulators) in a nice way.  If
	       not, you	can build such a script	using the xinit	program.  This
	       utility	simply	runs  one  user-specified program to start the
	       server, runs another to start up	any desired clients, and  then
	       waits  for either to finish.  Since either or both of the user-
	       specified programs may be a shell script, this  gives  substan-
	       tial  flexibility at the	expense	of a nice interface.  For this
	       reason, xinit is	not intended for end users.

       From the	user's perspective, every X server has a display name  of  the


       This  information is used by the	application to determine how it	should
       connect to the server and which screen it should	 use  by  default  (on
       displays	with multiple monitors):

	       The  protocol  specifies	the protocol to	use for	communication.
	       Exactly which protocols are supported  is  platform  dependent,
	       but most	commonly supported ones	are:

	       tcp     TCP over	IPv4 or	IPv6
	       inet    TCP over	IPv4 only
	       inet6   TCP over	IPv6 only
	       unix    UNIX Domain Sockets (same host only)
	       local   Platform	preferred local	connection method
	       If  the	protocol  is  not specified, Xlib uses whatever	it be-
	       lieves is the most efficient transport.

	       The hostname specifies the name of the  machine	to  which  the
	       display is physically connected.	 If the	hostname is not	given,
	       a connection to a server	on the same machine will be used.

	       The phrase "display" is usually used to refer to	 a  collection
	       of monitors that	share a	common set of input devices (keyboard,
	       mouse, tablet, etc.).  Most workstations	tend to	only have  one
	       display.	  Larger, multi-user systems, however, frequently have
	       several displays	so that	more than  one	person	can  be	 doing
	       graphics	 work  at once.	 To avoid confusion, each display on a
	       machine is assigned a display number (beginning at 0) when  the
	       X  server for that display is started.  The display number must
	       always be given in a display name.

	       Some displays share their input devices among two or more moni-
	       tors.   These  may  be  configured  as a	single logical screen,
	       which allows windows to move across screens, or	as  individual
	       screens,	 each  with  their  own	set of windows.	 If configured
	       such that each monitor has its own set of windows, each	screen
	       is  assigned a screen number (beginning at 0) when the X	server
	       for that	display	is started.   If  the  screen  number  is  not
	       given, screen 0 will be used.

       On  POSIX  systems,  the	default	display	name is	stored in your DISPLAY
       environment variable.  This variable is set automatically by the	 xterm
       terminal	 emulator.   However,  when  you log into another machine on a
       network,	you may	need to	set DISPLAY by hand to point to	your  display.
       For example,

	   % setenv DISPLAY myws:0
	   $ DISPLAY=myws:0; export DISPLAY

       The  ssh	program	can be used to start an	X program on a remote machine;
       it automatically	sets the DISPLAY variable correctly.

       Finally,	most X programs	accept a command line option of	-display  dis-
       playname	to temporarily override	the contents of	DISPLAY.  This is most
       commonly	used to	pop windows on another person's	screen or as part of a
       "remote shell" command to start an xterm	pointing back to your display.
       For example,

	   % xeyes -display joesws:0 -geometry 1000x1000+0+0
	   % rsh big xterm -display myws:0 -ls </dev/null &

       X servers listen	for connections	on a variety of	 different  communica-
       tions  channels	(network  byte	streams,  shared memory, etc.).	 Since
       there can be more than one way of contacting a given server, The	 host-
       name  part of the display name is used to determine the type of channel
       (also called a transport	layer) to be used.  X servers  generally  sup-
       port the	following types	of connections:

	       The  hostname  part  of	the  display  name should be the empty
	       string.	For example:  :0, :1, and :0.1.	  The  most  efficient
	       local transport will be chosen.

	       The  hostname part of the display name should be	the server ma-
	       chine's hostname	or IP address.	Full Internet names,  abbrevi-
	       ated names, IPv4	addresses, and IPv6 addresses are all allowed.
	       For example:, expo:0, [::1]:0,,	bigma-
	       chine:1,	and hydra:0.1.

       For  operating  systems	that support local connections other than Unix
       Domain sockets (SVR3 and	SVR4), there is	a compiled-in list  specifying
       the  order  in  which local connections should be attempted.  This list
       can be overridden by the	XLOCAL environment variable  described	below.
       If  the	display	name indicates a best-choice connection	should be made
       (e.g.  :0.0), each connection mechanism is  tried  until	 a  connection
       succeeds	or no more mechanisms are available.

       The  XLOCAL environment variable	should contain a list of one more more
       of the following:


       which represent SVR4 Named Streams pipe,	Old-style  USL	Streams	 pipe,
       SCO  XSight  Streams  pipe, and Unix domain sockets, respectively.  You
       can select a single mechanism (e.g.  XLOCAL=NAMED), or an ordered  list
       (e.g. XLOCAL="NAMED:PTS:SCO").  This variable overrides the compiled-in
       defaults.  For SVR4 it is recommended that NAMED	be the	first  prefer-
       ence connection.	 The default setting is	platform-dependent.

       To  globally  override the compiled-in defaults,	you should define (and
       export if using sh or ksh) XLOCAL globally.  If you  use	 startx(1)  or
       xinit(1),  the  definition  should be at	the top	of your	.xinitrc file.
       If you use xdm(1), the definitions should be early on in	 the  /usr/lo-
       cal/lib/X11/xdm/Xsession	script.

       An  X  server can use several types of access control.  Mechanisms pro-
       vided in	Release	7 are:

       Host Access	     Simple host-based access control.
       MIT-MAGIC-COOKIE-1    Shared plain-text "cookies".
       XDM-AUTHORIZATION-1   Secure DES	based private-keys.
       SUN-DES-1	     Based on Sun's secure rpc system.
       Server Interpreted    Server-dependent methods of access	control

       Xdm initializes access control for the server and  also	places	autho-
       rization	information in a file accessible to the	user.

       Normally,  the list of hosts from which connections are always accepted
       should be empty,	so that	only clients with  are	explicitly  authorized
       can  connect  to	 the  display.	 When you add entries to the host list
       (with xhost), the server	no longer performs any authorization  on  con-
       nections	from those machines.  Be careful with this.

       The  file  from which Xlib extracts authorization data can be specified
       with the	environment variable XAUTHORITY,  and  defaults	 to  the  file
       .Xauthority in the home directory.  Xdm uses $HOME/.Xauthority and will
       create it or merge in authorization records if it already exists	when a
       user logs in.

       If  you	use  several machines and share	a common home directory	across
       all of the machines by means of a network file system, you never	really
       have  to	 worry	about authorization files, the system should work cor-
       rectly by default.  Otherwise, as the authorization files are  machine-
       independent,  you  can  simply copy the files to	share them.  To	manage
       authorization files, use	xauth.	This program  allows  you  to  extract
       records and insert them into other files.  Using	this, you can send au-
       thorization to remote machines when you login, if  the  remote  machine
       does  not  share	a common home directory	with your local	machine.  Note
       that authorization information transmitted ``in the clear''  through  a
       network	file system or using ftp or rcp	can be ``stolen'' by a network
       eavesdropper, and as such may enable unauthorized access.  In many  en-
       vironments,  this level of security is not a concern, but if it is, you
       need to know the	exact semantics	of the particular  authorization  data
       to know if this is actually a problem.

       For  more  information  on  access control, see the Xsecurity(7)	manual

       One of the advantages of	using window systems instead of	hardwired ter-
       minals is that applications don't have to be restricted to a particular
       size or location	on the screen.	Although the layout of	windows	 on  a
       display	is  controlled	by the window manager that the user is running
       (described below), most X programs accept a command  line  argument  of
       the  form  -geometry WIDTHxHEIGHT+XOFF+YOFF (where WIDTH, HEIGHT, XOFF,
       and YOFF	are numbers) for specifying a preferred	size and location  for
       this application's main window.

       The  WIDTH  and	HEIGHT parts of	the geometry specification are usually
       measured	in either pixels or characters,	depending on the  application.
       The  XOFF and YOFF parts	are measured in	pixels and are used to specify
       the distance of the window from the left	or right and  top  and	bottom
       edges  of the screen, respectively.  Both types of offsets are measured
       from the	indicated edge of the screen to	the corresponding edge of  the
       window.	The X offset may be specified in the following ways:

       +XOFF   The left	edge of	the window is to be placed XOFF	pixels in from
	       the left	edge of	the screen (i.e., the X	coordinate of the win-
	       dow's  origin  will  be	XOFF).	XOFF may be negative, in which
	       case the	window's left edge will	be off the screen.

       -XOFF   The right edge of the window is to be  placed  XOFF  pixels  in
	       from  the  right	 edge of the screen.  XOFF may be negative, in
	       which case the window's right edge will be off the screen.

       The Y offset has	similar	meanings:

       +YOFF   The top edge of the window is to	be YOFF	pixels below  the  top
	       edge of the screen (i.e., the Y coordinate of the window's ori-
	       gin will	be YOFF).  YOFF	may be negative,  in  which  case  the
	       window's	top edge will be off the screen.

       -YOFF   The  bottom  edge  of the window	is to be YOFF pixels above the
	       bottom edge of the screen.  YOFF	may be negative, in which case
	       the window's bottom edge	will be	off the	screen.

       Offsets must be given as	pairs; in other	words, in order	to specify ei-
       ther XOFF or YOFF both must be present.	Windows	can be placed  in  the
       four corners of the screen using	the following specifications:

       +0+0    upper left hand corner.

       -0+0    upper right hand	corner.

       -0-0    lower right hand	corner.

       +0-0    lower left hand corner.

       In the following	examples, a terminal emulator is placed	in roughly the
       center of the screen and	a load average monitor,	mailbox, and clock are
       placed in the upper right hand corner:

	   xterm -fn 6x10 -geometry 80x24+30+200 &
	   xclock -geometry 48x48-0+0 &
	   xload -geometry 48x48-96+0 &
	   xbiff -geometry 48x48-48+0 &

       The  layout  of windows on the screen is	controlled by special programs
       called window managers.	Although many window managers will honor geom-
       etry specifications as given, others may	choose to ignore them (requir-
       ing the user to explicitly draw the window's region on the screen  with
       the pointer, for	example).

       Since  window  managers are regular (albeit complex) client programs, a
       variety of different user interfaces can	be built.  The	X.Org  Founda-
       tion  provides  a  window  manager named	twm which supports overlapping
       windows,	popup menus, point-and-click or	 click-to-type	input  models,
       title  bars,  nice  icons (and an icon manager for those	who don't like
       separate	icon windows).

       See your	distro package manager for other popular window	managers.

       Collections of characters for displaying	text  and  symbols  in	X  are
       known  as  fonts.  A font typically contains images that	share a	common
       appearance and look nice	together (for example, a  single  size,	 bold-
       ness,  slant, and character set).  Similarly, collections of fonts that
       are based on a common type face (the variations are usually called  ro-
       man,  bold,  italic, bold italic, oblique, and bold oblique) are	called

       Fonts come in various sizes.  The X  server  supports  scalable	fonts,
       meaning it is possible to create	a font of arbitrary size from a	single
       source for the font.  The server	supports scaling  from	outline	 fonts
       and bitmap fonts.  Scaling from outline fonts usually produces signifi-
       cantly better results than scaling from bitmap fonts.

       An X server can obtain fonts from individual files stored  in  directo-
       ries  in	 the  file system, or from one or more font servers, or	from a
       mixtures	of directories and font	 servers.   The	 list  of  places  the
       server looks when trying	to find	a font is controlled by	its font path.
       Although	most installations will	choose to have	the  server  start  up
       with  all  of  the commonly used	font directories in the	font path, the
       font path can be	changed	at any time with the xset  program.   However,
       it  is  important  to  remember	that  the  directory  names are	on the
       server's	machine, not on	the application's.

       Bitmap font files are usually created by	compiling a textual  font  de-
       scription into binary form, using bdftopcf.  Font databases are created
       by running the mkfontdir	program	in the directory containing the	source
       or  compiled  versions of the fonts.  Whenever fonts are	added to a di-
       rectory,	mkfontdir should be rerun so that the server can find the  new
       fonts.	To  make  the  server reread the font database,	reset the font
       path with the xset program.  For	example, to add	a font	to  a  private
       directory, the following	commands could be used:

	   % cp	newfont.pcf ~/myfonts
	   % mkfontdir ~/myfonts
	   % xset fp rehash

       The  xfontsel  and  xlsfonts programs can be used to browse through the
       fonts available on a server.  Font names	tend to	be fairly long as they
       contain	all  of	the information	needed to uniquely identify individual
       fonts.  However,	the X server supports wildcarding of  font  names,  so
       the full	specification


       might be	abbreviated as:


       Because	the  shell  also  has special meanings for * and ?, wildcarded
       font names should be quoted:

	   % xlsfonts -fn '-*-courier-medium-r-normal--*-100-*-*-*-*-*-*'

       The xlsfonts program can	be used	to list	all of the fonts that match  a
       given  pattern.	With no	arguments, it lists all	available fonts.  This
       will usually list the same font at many different sizes.	 To  see  just
       the base	scalable font names, try using one of the following patterns:


       To  convert  one	of the resulting names into a font at a	specific size,
       replace one of the first	two zeros with a  nonzero  value.   The	 field
       containing the first zero is for	the pixel size;	replace	it with	a spe-
       cific height in pixels to name a	font at	that size.  Alternatively, the
       field containing	the second zero	is for the point size; replace it with
       a specific size in decipoints (there are	722.7 decipoints to the	 inch)
       to  name	a font at that size.  The last zero is an average width	field,
       measured	in tenths of pixels; some servers will anamorphically scale if
       this value is specified.

       One  of	the following forms can	be used	to name	a font server that ac-
       cepts TCP connections:


       The hostname specifies the name (or decimal numeric address) of the ma-
       chine on	which the font server is running.  The port is the decimal TCP
       port on which the font server is	listening for connections.  The	 cata-
       loguelist specifies a list of catalogue names, with '+' as a separator.

       Examples: tcp/, tcp/

       Most  applications provide ways of tailoring (usually through resources
       or command line arguments) the colors of	various	elements in  the  text
       and  graphics  they display.  A color can be specified either by	an ab-
       stract color name, or by	a numerical color specification.  The  numeri-
       cal specification can identify a	color in either	device-dependent (RGB)
       or device-independent terms.  Color strings are case-insensitive.

       X supports the use of abstract color names, for example,	"red", "blue".
       A  value	 for  this  abstract name is obtained by searching one or more
       color name databases.  Xlib first searches  zero	 or  more  client-side
       databases;  the number, location, and content of	these databases	is im-
       plementation dependent.	If the name is not found, the color is	looked
       up  in the X server's database.	The text form of this database is com-
       monly stored in the file	/usr/local/share/X11/rgb.txt.

       A numerical color specification consists	of a color space  name	and  a
       set of values in	the following syntax:


       An  RGB Device specification is identified by the prefix	"rgb:" and has
       the following syntax:


	       _red_, _green_, _blue_ := h | hh	| hhh |	hhhh
	       h := single hexadecimal digits

       Note that h indicates the value scaled in 4 bits, hh the	 value	scaled
       in  8  bits, hhh	the value scaled in 12 bits, and hhhh the value	scaled
       in 16 bits, respectively.  These	values are passed directly  to	the  X
       server, and are assumed to be gamma corrected.

       The eight primary colors	can be represented as:

			    black     rgb:0/0/0
			    red	      rgb:ffff/0/0

			    green     rgb:0/ffff/0
			    blue      rgb:0/0/ffff
			    yellow    rgb:ffff/ffff/0
			    magenta   rgb:ffff/0/ffff
			    cyan      rgb:0/ffff/ffff
			    white     rgb:ffff/ffff/ffff

       For  backward  compatibility,  an  older	 syntax	for RGB	Device is sup-
       ported, but its continued use is	not encouraged.	 The syntax is an ini-
       tial  sharp  sign character followed by a numeric specification,	in one
       of the following	formats:

			   #RGB		   (4 bits each)
			   #RRGGBB	   (8 bits each)
			   #RRRGGGBBB	   (12 bits each)
			   #RRRRGGGGBBBB   (16 bits each)

       The R, G, and B represent single	hexadecimal digits.  When  fewer  than
       16 bits each are	specified, they	represent the most-significant bits of
       the value (unlike the "rgb:" syntax, in which values are	scaled).   For
       example,	#3a7 is	the same as #3000a0007000.

       An  RGB intensity specification is identified by	the prefix "rgbi:" and
       has the following syntax:


       The red,	green, and blue	are floating point values between 0.0 and 1.0,
       inclusive.  They	represent linear intensity values, with	1.0 indicating
       full intensity, 0.5 half	intensity, and so on.  These  values  will  be
       gamma  corrected	 by Xlib before	being sent to the X server.  The input
       format for these	values is an optional sign, a string of	numbers	possi-
       bly containing a	decimal	point, and an optional exponent	field contain-
       ing an E	or e followed by a possibly signed integer string.

       The standard device-independent string specifications have the  follow-
       ing syntax:

		       CIEXYZ:_X_/_Y_/_Z_   (none, 1, none)
		       CIEuvY:_u_/_v_/_Y_   (~.6, ~.6, 1)
		       CIExyY:_x_/_y_/_Y_   (~.75, ~.85, 1)
		       CIELab:_L_/_a_/_b_   (100, none,	none)
		       CIELuv:_L_/_u_/_v_   (100, none,	none)
		       TekHVC:_H_/_V_/_C_   (360, 100, 100)

       All  of	the  values  (C, H, V, X, Y, Z,	a, b, u, v, y, x) are floating
       point values.  Some of the values are constrained to  be	 between  zero
       and  some upper bound; the upper	bounds are given in parentheses	above.
       The syntax for these values is an optional '+' or '-' sign, a string of
       digits  possibly	 containing  a decimal point, and an optional exponent
       field consisting	of an 'E' or 'e' followed by an	optional  '+'  or  '-'
       followed	by a string of digits.

       For  more  information on device	independent color, see the Xlib	refer-
       ence manual.

       The X keyboard model is broken into two layers:	server-specific	 codes
       (called	keycodes)  which represent the physical	keys, and server-inde-
       pendent symbols (called keysyms)	which represent	the letters  or	 words
       that  appear  on	 the keys.  Two	tables are kept	in the server for con-
       verting keycodes	to keysyms:

       modifier	list
	       Some keys (such as Shift, Control, and Caps Lock) are known  as
	       modifier	 and are used to select	different symbols that are at-
	       tached to a single key (such as Shift-a generates a capital  A,
	       and  Control-l  generates  a control character ^L).  The	server
	       keeps a list of keycodes	corresponding to the various  modifier
	       keys.  Whenever a key is	pressed	or released, the server	gener-
	       ates an event that contains the keycode of the indicated	key as
	       well  as	 a  mask that specifies	which of the modifier keys are
	       currently pressed.  Most	servers	set up this list to  initially
	       contain	the various shift, control, and	shift lock keys	on the

       keymap table
	       Applications translate event keycodes and modifier  masks  into
	       keysyms	using  a  keysym table which contains one row for each
	       keycode and one column for various modifier states.  This table
	       is initialized by the server to correspond to normal typewriter
	       conventions.  The exact semantics of how	the  table  is	inter-
	       preted  to  produce  keysyms depends on the particular program,
	       libraries, and language input method used,  but	the  following
	       conventions  for	 the first four	keysyms	in each	row are	gener-
	       ally adhered to:

       The first four elements of the  list  are  split	 into  two  groups  of
       keysyms.	  Group	 1 contains the	first and second keysyms; Group	2 con-
       tains the third and fourth keysyms.  Within each	group,	if  the	 first
       element	is alphabetic and the the second element is the	special	keysym
       NoSymbol, then the group	is treated as equivalent to a group  in	 which
       the first element is the	lowercase letter and the second	element	is the
       uppercase letter.

       Switching between groups	is controlled by the keysym named MODE SWITCH,
       by  attaching that keysym to some key and attaching that	key to any one
       of the modifiers	Mod1  through  Mod5.   This  modifier  is  called  the
       ``group	modifier.''   Group  1 is used when the	group modifier is off,
       and Group 2 is used when	the group modifier is on.

       Within a	group, the modifier state determines which keysym to use.  The
       first  keysym  is  used when the	Shift and Lock modifiers are off.  The
       second keysym is	used when the Shift modifier is	on, when the Lock mod-
       ifier  is on and	the second keysym is uppercase alphabetic, or when the
       Lock modifier is	on and is interpreted as ShiftLock.   Otherwise,  when
       the  Lock  modifier  is on and is interpreted as	CapsLock, the state of
       the Shift modifier is applied first to select a	keysym;	 but  if  that
       keysym is lowercase alphabetic, then the	corresponding uppercase	keysym
       is used instead.

       Most X programs attempt to use the same names for command line  options
       and  arguments.	All applications written with the X Toolkit Intrinsics
       automatically accept the	following options:

       -display	display
	       This option specifies the name of the X server to use.

       -geometry geometry
	       This option specifies the initial size and location of the win-

       -bg color, -background color
	       Either  option  specifies the color to use for the window back-

       -bd color, -bordercolor color
	       Either option specifies the color to use	for the	window border.

       -bw number, -borderwidth	number
	       Either option specifies the width in pixels of the window  bor-

       -fg color, -foreground color
	       Either option specifies the color to use	for text or graphics.

       -fn font, -font font
	       Either option specifies the font	to use for displaying text.

	       This  option  indicates that the	user would prefer that the ap-
	       plication's windows initially not be visible as if the  windows
	       had  be immediately iconified by	the user.  Window managers may
	       choose not to honor the application's request.

	       This option specifies the name under which  resources  for  the
	       application  should  be	found.	This option is useful in shell
	       aliases to distinguish between invocations of  an  application,
	       without	resorting  to  creating	 links to alter	the executable
	       file name.

       -rv, -reverse
	       Either option indicates that the	program	 should	 simulate  re-
	       verse  video  if	possible, often	by swapping the	foreground and
	       background colors.  Not all programs honor this or implement it
	       correctly.  It is usually only used on monochrome displays.

	       This  option indicates that the program should not simulate re-
	       verse video.  This is used to override any defaults  since  re-
	       verse video doesn't always work properly.

	       This  option specifies the timeout in milliseconds within which
	       two communicating applications must respond to one another  for
	       a selection request.

	       This  option  indicates that requests to	the X server should be
	       sent synchronously, instead of asynchronously.  Since Xlib nor-
	       mally buffers requests to the server, errors do not necessarily
	       get reported immediately	after they occur.  This	 option	 turns
	       off  the	buffering so that the application can be debugged.  It
	       should never be used with a working program.

       -title string
	       This option specifies the title to be  used  for	 this  window.
	       This  information is sometimes used by a	window manager to pro-
	       vide some sort of header	identifying the	window.

       -xnllanguage language[_territory][.codeset]
	       This option specifies the language, territory, and codeset  for
	       use in resolving	resource and other filenames.

       -xrm resourcestring
	       This option specifies a resource	name and value to override any
	       defaults.  It is	also very useful for  setting  resources  that
	       don't have explicit command line	arguments.

       To make the tailoring of	applications to	personal preferences easier, X
       provides	a mechanism for	storing	default	values for  program  resources
       (e.g.  background  color,  window title,	etc.) that is used by programs
       that use	toolkits based on the  X  Toolkit  Intrinsics  library	libXt.
       (Programs using the common Gtk+ and Qt toolkits use other configuration
       mechanisms.)  Resources are specified as	strings	that are read in  from
       various	places	when  an  application  is run.	Program	components are
       named in	a hierarchical fashion,	with each node in the hierarchy	 iden-
       tified  by a class and an instance name.	 At the	top level is the class
       and instance name of the	application itself.  By	convention, the	 class
       name  of	the application	is the same as the program name, but with  the
       first letter capitalized	(e.g. Bitmap or	Emacs) although	some  programs
       that  begin with	the letter ``x'' also capitalize the second letter for
       historical reasons.

       The precise syntax for resources	is:

       ResourceLine    =       Comment | IncludeFile | ResourceSpec | <empty line>
       Comment	       =       "!" {<any character except null or newline>}
       IncludeFile     =       "#" WhiteSpace "include"	WhiteSpace FileName WhiteSpace
       FileName	       =       <valid filename for operating system>
       ResourceSpec    =       WhiteSpace ResourceName WhiteSpace ":" WhiteSpace Value
       ResourceName    =       [Binding] {Component Binding} ComponentName
       Binding	       =       "." | "*"
       WhiteSpace      =       {<space>	| <horizontal tab>}
       Component       =       "?" | ComponentName
       ComponentName   =       NameChar	{NameChar}
       NameChar	       =       "a"-"z" | "A"-"Z" | "0"-"9" | "_" | "-"
       Value	       =       {<any character except null or unescaped	newline>}

       Elements	separated by vertical bar (|) are alternatives.	 Curly	braces
       ({...})	indicate  zero	or  more repetitions of	the enclosed elements.
       Square brackets ([...]) indicate	that the enclosed element is optional.
       Quotes ("...") are used around literal characters.

       IncludeFile  lines  are interpreted by replacing	the line with the con-
       tents of	the specified file.  The word "include"	must be	in  lowercase.
       The  filename  is  interpreted relative to the directory	of the file in
       which the line occurs (for example, if the filename contains no	direc-
       tory or contains	a relative directory specification).

       If a ResourceName contains a contiguous sequence	of two or more Binding
       characters, the sequence	will be	replaced with single "." character  if
       the  sequence contains only "." characters, otherwise the sequence will
       be replaced with	a single "*" character.

       A resource database never contains more than one	entry for a given  Re-
       sourceName.   If	 a resource file contains multiple lines with the same
       ResourceName, the last line in the file is used.

       Any whitespace character	before or after	the name or  colon  in	a  Re-
       sourceSpec are ignored.	To allow a Value to begin with whitespace, the
       two-character sequence ``\space'' (backslash followed by	space) is rec-
       ognized	and  replaced  by a space character, and the two-character se-
       quence ``\tab'' (backslash followed by horizontal  tab)	is  recognized
       and  replaced  by a horizontal tab character.  To allow a Value to con-
       tain embedded newline characters, the two-character sequence ``\n''  is
       recognized and replaced by a newline character.	To allow a Value to be
       broken across multiple lines in a text file, the	two-character sequence
       ``\newline''  (backslash	followed by newline) is	recognized and removed
       from the	value.	To allow a Value to contain arbitrary character	codes,
       the four-character sequence ``\nnn'', where each	n is a digit character
       in the range of ``0''-``7'', is recognized and replaced with  a	single
       byte that contains the octal value specified by the sequence.  Finally,
       the two-character sequence ``\\'' is recognized	and  replaced  with  a
       single backslash.

       When  an	 application looks for the value of a resource,	it specifies a
       complete	path in	the hierarchy, with both  class	 and  instance	names.
       However,	 resource  values are usually given with only partially	speci-
       fied names and classes, using pattern matching constructs.  An asterisk
       (*) is a	loose binding and is used to represent any number of interven-
       ing components, including none.	A period (.) is	a tight	binding	and is
       used  to	separate immediately adjacent components.  A question mark (?)
       is used to match	any single component name or class.  A database	 entry
       cannot  end  in	a  loose binding; the final component (which cannot be
       "?") must be specified.	The lookup  algorithm  searches	 the  resource
       database	for the	entry that most	closely	matches	(is most specific for)
       the full	name and class being queried.  When more than one database en-
       try  matches  the full name and class, precedence rules are used	to se-
       lect just one.

       The full	name and class are scanned from	left to	 right	(from  highest
       level  in  the  hierarchy to lowest), one component at a	time.  At each
       level, the corresponding	component and/or binding of each matching  en-
       try  is determined, and these matching components and bindings are com-
       pared according to precedence rules.  Each of the rules is  applied  at
       each  level,  before  moving  to	the next level,	until a	rule selects a
       single entry over all others.  The rules	(in order of precedence) are:

       1.   An entry that contains a matching component	(whether name,	class,
	    or	"?")  takes precedence over entries that elide the level (that
	    is,	entries	that match the level in	a loose	binding).

       2.   An entry with a matching name takes	precedence over	 both  entries
	    with  a matching class and entries that match using	"?".  An entry
	    with a matching class takes	precedence over	entries	that match us-
	    ing	"?".

       3.   An entry preceded by a tight binding takes precedence over entries
	    preceded by	a loose	binding.

       Programs	based on the X Toolkit Intrinsics obtain  resources  from  the
       following  sources (other programs usually support some subset of these

       RESOURCE_MANAGER	root window property
	       Any global resources that should	be available to	clients	on all
	       machines	 should	 be stored in the RESOURCE_MANAGER property on
	       the root	window of the first screen  using  the	xrdb  program.
	       This  is	 frequently  taken  care  of when the user starts up X
	       through the display manager or xinit.

       SCREEN_RESOURCES	root window property
	       Any resources specific to a given  screen  (e.g.	 colors)  that
	       should be available to clients on all machines should be	stored
	       in the SCREEN_RESOURCES property	on the	root  window  of  that
	       screen.	The xrdb program will sort resources automatically and
	       place them in RESOURCE_MANAGER or SCREEN_RESOURCES,  as	appro-

       application-specific files
	       Directories  named by the environment variable XUSERFILESEARCH-
	       PATH or the environment variable	 XAPPLRESDIR  (which  names  a
	       single  directory  and should end with a	'/' on POSIX systems),
	       plus directories	in a standard place  (usually  under  /usr/lo-
	       cal/share/X11/,	but  this  can	be  overridden with the	XFILE-
	       SEARCHPATH environment variable)	are searched for for  applica-
	       tion-specific  resources.  For example, application default re-
	       sources are usually kept	in /usr/local/share/X11/app-defaults/.
	       See  the	X Toolkit Intrinsics - C Language Interface manual for

	       Any user- and machine-specific resources	may  be	 specified  by
	       setting	the XENVIRONMENT environment variable to the name of a
	       resource	file to	be loaded by all applications.	If this	 vari-
	       able  is	not defined, a file named $HOME/.Xdefaults-hostname is
	       looked for instead, where hostname is  the  name	 of  the  host
	       where the application is	executing.

       -xrm resourcestring
	       Resources can also be specified from the	command	line.  The re-
	       sourcestring is a single	 resource  name	 and  value  as	 shown
	       above.  Note that if the	string contains	characters interpreted
	       by the shell (e.g., asterisk), they must	be quoted.  Any	number
	       of -xrm arguments may be	given on the command line.

       Program	resources  are	organized  into	groups called classes, so that
       collections of individual resources  (each  of  which  are  called  in-
       stances)	can be set all at once.	 By convention,	the instance name of a
       resource	begins with a lowercase	letter and class name  with  an	 upper
       case  letter.   Multiple	word resources are concatenated	with the first
       letter of the succeeding	words capitalized.  Applications written  with
       the X Toolkit Intrinsics	will have at least the following resources:

       background (class Background)
	       This  resource  specifies the color to use for the window back-

       borderWidth (class BorderWidth)
	       This resource specifies the width in pixels of the window  bor-

       borderColor (class BorderColor)
	       This resource specifies the color to use	for the	window border.

       Most applications using the X Toolkit Intrinsics	also have the resource
       foreground (class Foreground), specifying the color to use for text and
       graphics	within the window.

       By combining class and instance specifications, application preferences
       can be set quickly and easily.  Users of	color displays will frequently
       want  to	 set Background	and Foreground classes to particular defaults.
       Specific	color instances	such as	text cursors can  then	be  overridden
       without having to define	all of the related resources.  For example,

	   bitmap*Dashed:  off
	   XTerm*cursorColor:  gold
	   XTerm*multiScroll:  on
	   XTerm*jumpScroll:  on
	   XTerm*reverseWrap:  on
	   XTerm*curses:  on
	   XTerm*Font:	6x10
	   XTerm*scrollBar: on
	   XTerm*scrollbar*thickness: 5
	   XTerm*multiClickTime: 500
	   XTerm*charClass:  33:48,37:48,45-47:48,64:48
	   XTerm*cutNewline: off
	   XTerm*cutToBeginningOfLine: off
	   XTerm*titeInhibit:  on
	   XTerm*ttyModes:  intr ^c erase ^? kill ^u
	   XLoad*Background: gold
	   XLoad*Foreground: red
	   XLoad*highlight: black
	   XLoad*borderWidth: 0
	   emacs*Geometry:  80x65-0-0
	   emacs*Background:  rgb:5b/76/86
	   emacs*Foreground:  white
	   emacs*Cursor:  white
	   emacs*BorderColor:  white
	   emacs*Font:	6x10
	   xmag*geometry: -0-0
	   xmag*borderColor:  white

       If  these  resources  were  stored in a file called .Xresources in your
       home directory, they could be added to any existing  resources  in  the
       server with the following command:

	   % xrdb -merge $HOME/.Xresources

       This  is	 frequently  how user-friendly startup scripts merge user-spe-
       cific defaults into any site-wide defaults.  All	sites  are  encouraged
       to  set	up convenient ways of automatically loading resources. See the
       Xlib manual section Resource Manager Functions for more information.

	      This is the only mandatory environment variable. It  must	 point
	      to an X server. See section "Display Names" above.

	      This  must point to a file that contains authorization data. The
	      default  is  $HOME/.Xauthority.  See   Xsecurity(7),   xauth(1),
	      xdm(1), Xau(3).

	      This  must point to a file that contains authorization data. The
	      default is $HOME/.ICEauthority.

	      The first	non-empty value	among these three determines the  cur-
	      rent  locale's  facet  for character handling, and in particular
	      the default text	encoding.  See	locale(7),  setlocale(3),  lo-

	      This  variable  can be set to contain additional information im-
	      portant  for  the	 current  locale  setting.  Typically  set  to
	      @im=_input-method_  to  enable  a	 particular  input method. See

	      This must	point to a directory containing	the locale.alias  file
	      and Compose and XLC_LOCALE file hierarchies for all locales. The
	      default value is /usr/local/share/X11/locale.

	      This must	point to a file	containing X resources.	The default is
	      $HOME/.Xdefaults-_hostname_.  Unlike  $HOME/.Xresources,	it  is
	      consulted	each time an X application starts.

	      This must	contain	a colon	 separated  list  of  path  templates,
	      where  libXt  will  search for resource files. The default value
	      consists of


	      A	path template is transformed to	a pathname by substituting:

		  %D =>	the implementation-specific default path
		  %N =>	name (basename)	being searched for
		  %T =>	type (dirname) being searched for
		  %S =>	suffix being searched for
		  %C =>	value of the resource "customization"
			(class "Customization")
		  %L =>	the locale name
		  %l =>	the locale's language (part before '_')
		  %t =>	the locale's territory (part after '_` but before '.')
		  %c =>	the locale's encoding (part after '.')

	      This must	contain	a colon	 separated  list  of  path  templates,
	      where  libXt  will search	for user dependent resource files. The
	      default value is:


	      $XAPPLRESDIR defaults to $HOME, see below.

	      A	path template is transformed to	a pathname by substituting:

		  %D =>	the implementation-specific default path
		  %N =>	name (basename)	being searched for
		  %T =>	type (dirname) being searched for
		  %S =>	suffix being searched for
		  %C =>	value of the resource "customization"
			(class "Customization")
		  %L =>	the locale name
		  %l =>	the locale's language (part before '_')
		  %t =>	the locale's territory (part after '_` but before '.')
		  %c =>	the locale's encoding (part after '.')

	      This must	point to a base	directory where	the  user  stores  the
	      application  dependent  resource	files.	The  default  value is
	      $HOME. Only used if XUSERFILESEARCHPATH is not set.

	      This must	point to a file	containing nonstandard keysym  defini-
	      tions.  The default value	is /usr/local/share/X11/XKeysymDB.

       XCMSDB This must	point to a color name database file. The default value

	      This serves as main identifier for resources  belonging  to  the
	      program  being executed. It defaults to the basename of pathname
	      of the program.

	      Denotes the session manager to which the application should con-
	      nect. See	xsm(1),	rstart(1).

	      Setting	this  variable	to  a  non-empty  value	 disables  the
	      XFree86-Bigfont extension. This extension	is a mechanism to  re-
	      duce  the	 memory	consumption of big fonts by use	of shared mem-


       These variables influence the X Keyboard	Extension.

       The following is	a collection of	sample command lines for some  of  the
       more  frequently	 used  commands.  For more information on a particular
       command,	please refer to	that command's manual page.

	   %  xrdb $HOME/.Xresources
	   %  xmodmap -e "keysym BackSpace = Delete"
	   %  mkfontdir	/usr/local/lib/X11/otherfonts
	   %  xset fp+ /usr/local/lib/X11/otherfonts
	   %  xmodmap $HOME/
	   %  xsetroot -solid 'rgbi:.8/.8/.8'
	   %  xset b 100 400 c 50 s 1800 r on
	   %  xset q
	   %  twm
	   %  xmag
	   %  xclock -geometry 48x48-0+0 -bg blue -fg white
	   %  xeyes -geometry 48x48-48+0
	   %  xbiff -update 20
	   %  xlsfonts '*helvetica*'
	   %  xwininfo -root
	   %  xdpyinfo -display	joesworkstation:0
	   %  xhost -joesworkstation
	   %  xrefresh
	   %  xwd | xwud
	   %  bitmap 32x32
	   %  xcalc -bg	blue -fg magenta
	   %  xterm -geometry 80x66-0-0	-name myxterm $*

       A wide variety of error messages	are generated from  various  programs.
       The  default  error  handler  in	Xlib (also used	by many	toolkits) uses
       standard	resources to construct diagnostic messages when	errors	occur.
       The  defaults  for  these  messages  are	 usually  stored  in  /usr/lo-
       cal/share/X11/XErrorDB.	If this	file is	not  present,  error  messages
       will be rather terse and	cryptic.

       When  the  X  Toolkit  Intrinsics  encounter errors converting resource
       strings to the appropriate internal format, no error messages are  usu-
       ally  printed.  This is convenient when it is desirable to have one set
       of resources across a variety of	displays (e.g. color  vs.  monochrome,
       lots  of	 fonts	vs. very few, etc.), although it can pose problems for
       trying to determine why an application might be failing.	 This behavior
       can be overridden by the	setting	the StringConversionWarnings resource.

       To force	the X Toolkit Intrinsics to always print string	conversion er-
       ror messages, the following resource should be placed in	the file  that
       gets  loaded  onto the RESOURCE_MANAGER property	using the xrdb program
       (frequently called .Xresources or .Xres in the user's home directory):

	   *StringConversionWarnings: on

       To have conversion messages printed for just a particular  application,
       the appropriate instance	name can be placed before the asterisk:

	   xterm*StringConversionWarnings: on

       XOrgFoundation(7), XStandards(7), Xsecurity(7), appres(1), bdftopcf(1),
       bitmap(1), editres(1), fslsfonts(1),  fstobdf(1),  iceauth(1),  mkfont-
       dir(1),	 mkfontscale(1),  oclock(1),  rgb(1),  resize(1),  smproxy(1),
       transset(1),  twm(1),  x11perf(1),  x11perfcomp(1),  xauth(1),	xclip-
       board(1), xclock(1), xcmsdb(1), xcompmgr(1), xconsole(1), xdm(1), xdpy-
       info(1),	xdriinfo(1), xev(1), xfd(1), xfontsel(1), xfs(1),  xfsinfo(1),
       xhost(1), xinit(1), xkbbell(1), xkbcomp(1), xkbevd(1), xkbprint(1), xk-
       bvleds(1), xkbwatch(1), xkill(1), xlogo(1), xlsatoms(1),	xlsclients(1),
       xlsfonts(1),  xmag(1),  xmodmap(1),  xprop(1), xrandr(1), xrdb(1), xre-
       fresh(1), xrestop(1), xscope(1),	xset(1),  xsetroot(1),	xsm(1),	 xstd-
       cmap(1),	   xterm(1),	xvinfo(1),   xwd(1),   xwininfo(1),   xwud(1).
       Xserver(1), Xorg(1), Xdmx(1), Xephyr(1),	Xnest(1), Xquartz(1), Xvfb(1),
       Xvnc(1),	XWin(1).

       Xlib  -	C  Language X Interface, and X Toolkit Intrinsics - C Language

       Those specifications, and additional specifications & documentation for
       the X Window System may also be found in	/usr/local/share/doc or	on the
       X.Org Foundation	website	at <>.

       X Window	System is a trademark of The Open Group.

       A cast of thousands, literally.	Releases 6.7 and later are brought  to
       you  by the X.Org Foundation. The names of all people who made it a re-
       ality will be found in the individual documents and source files.

       Releases	6.6 and	6.5 were done by The X.Org  Group.   Release  6.4  was
       done  by	The X Project Team.  The Release 6.3 distribution was from The
       X Consortium, Inc.  The staff members at	the X  Consortium  responsible
       for that	release	were: Donna Converse (emeritus), Stephen Gildea	(emer-
       itus), Kaleb Keithley, Matt Landau (emeritus),  Ralph  Mor  (emeritus),
       Janet  O'Halloran, Bob Scheifler, Ralph Swick, Dave Wiggins (emeritus),
       and Reed	Augliere.

       The X Window System standard was	originally developed at	the Laboratory
       for  Computer Science at	the Massachusetts Institute of Technology, and
       all rights thereto were assigned	to the	X  Consortium  on  January  1,
       1994.   X  Consortium, Inc. closed its doors on December	31, 1996.  All
       rights to the X Window System have been assigned	to The Open Group.

X Version 11			xorg-docs 1.7.2				  X(7)


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