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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

       The number of programs that use X is quite large.  Programs provided in
       the core	X.Org Foundation distribution include:	a  terminal  emulator,
       xterm;  a  window manager, twm; a display manager, xdm; a console redi-
       rect program, xconsole; a mail interface, xmh; a	bitmap editor, bitmap;
       resource	 listing/manipulation  tools,  appres, editres;	access control
       programs, xauth,	xhost, and iceauth; user preference setting  programs,
       xrdb, xcmsdb, xset, xsetroot, xstdcmap, and xmodmap; clocks, xclock and
       oclock; a font displayer, xfd; utilities	for listing information	 about
       fonts, windows, and displays, xlsfonts, xwininfo, xlsclients, xdpyinfo,
       xlsatoms, and xprop; screen image manipulation  utilities,  xwd,	 xwud,
       and  xmag; a performance	measurement utility, x11perf; a	font compiler,
       bdftopcf; a font	server and related utilities, xfs, fsinfo,  fslsfonts,
       fstobdf;	 a display server and related utilities, Xserver, rgb, mkfont-
       dir; a clipboard	manager, xclipboard; keyboard description compiler and
       related	utilities,  xkbcomp, setxkbmap xkbprint, xkbbell, xkbevd, xkb-
       vleds, and xkbwatch; a utility to terminate clients, xkill; a  firewall
       security	 proxy,	 xfwp;	a  proxy manager to control them, proxymngr; a
       utility to find proxies,	xfindproxy; web	 browser  plug-ins,
       and;  an RX MIME-type helper program, xrx; 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  user-contributed software in	the X.Org Foundation distribu-
       tion, or	are available on the Internet.	See  your  site	 administrator
       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 hostname specifies the name of the  machine	to  which  the
	       display is physically connected.	 If the	hostname is not	given,
	       the most	efficient way of communicating 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.

       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  connections  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  distribution comes	with a window manager named twm	which supports
       overlapping windows, popup menus, point-and-click or click-to-type  in-
       put  models,  title bars, nice icons (and an icon manager for those who
       don't like separate icon	windows).

       See the user-contributed	software in the	X.Org Foundation  distribution
       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 his
	      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), fsinfo(1), fslsfonts(1), fstobdf(1), iceauth(1),
       imake(1), makedepend(1),	mkfontdir(1), oclock(1), proxymngr(1), rgb(1),
       resize(1),  rstart(1),  smproxy(1), twm(1), x11perf(1), x11perfcomp(1),
       xauth(1), xclipboard(1),	xclock(1), xcmsdb(1), xconsole(1), xdm(1), xd-
       pyinfo(1),  xfd(1), xfindproxy(1), xfs(1), xfwp(1), xhost(1), xinit(1),
       xkbbell(1),  xkbcomp(1),	 xkbevd(1),  xkbprint(1),  xkbvleds(1),	  xkb-
       watch(1),  xkill(1), xlogo(1), xlsatoms(1), xlsclients(1), xlsfonts(1),
       xmag(1),	xmh(1),	xmodmap(1), xprop(1),  xrdb(1),	 xrefresh(1),  xrx(1),
       xset(1),	 xsetroot(1),  xsm(1),	xstdcmap(1),  xterm(1),	 xwd(1), xwin-
       info(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 Interface

       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				  X(7)


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