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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 print server and	related	 utilities,  Xprt,  xplsprinters,  and
       xprehashprinterlist;  remote  execution	utilities,  rstart  and	xon; a
       clipboard manager, xclipboard; keyboard description  compiler  and  re-
       lated  utilities,  xkbcomp,  setxkbmap  xkbprint, xkbbell, xkbevd, xkb-
       vleds, and xkbwatch; a utility to terminate clients,  xkill;  an	 opti-
       mized  X	 protocol  proxy, lbxproxy; 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.

       xdm (the	X Display Manager)
	       If you want to always have X running on your display, your site
	       administrator can set your machine up to	use the	X Display Man-
	       ager  xdm.   This program is typically started by the system at
	       boot time and takes care	of keeping the server running and get-
	       ting  users  logged in.	If you are running xdm,	you will see a
	       window on the screen welcoming you to the system	and asking for
	       your  username  and password.  Simply type them in as you would
	       at a normal terminal, pressing the Return key after  each.   If
	       you  make  a mistake, xdm will display an error message and ask
	       you to try again.  After	you have successfully logged  in,  xdm
	       will  start  up your X environment.  By default,	if you have an
	       executable file named .xsession in  your	 home  directory,  xdm
	       will treat it as	a program (or shell script) to run to start up
	       your initial clients (such as  terminal	emulators,  clocks,  a
	       window  manager,	 user settings for things like the background,
	       the speed of the	pointer, etc.).	 Your site  administrator  can
	       provide 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	collection  of
	       monitors	 that  share  a	 common	 keyboard  and pointer (mouse,
	       tablet, etc.).  Most workstations tend to only  have  one  key-
	       board,  and  therefore,	only  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 num-
	       ber  (beginning	at  0)	when  the X server for that display is
	       started.	 The display number must always	be given in a  display

	       Some  displays share a single keyboard and pointer among	two or
	       more monitors.  Since 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 will need to set DISPLAY by	hand to	point to your display.
       For example,

	   % setenv DISPLAY myws:0
	   $ DISPLAY=myws:0; export DISPLAY
       The  xon	 script	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 IP address  name.   Full	 Internet  names,  abbreviated
	       names,	and  IP	 addresses  are	 all  allowed.	 For  example:,	expo:0,, bigmachine:1, and hydra:0.1.

	       The hostname part of the	display	name should be the server  ma-
	       chine's	nodename,  followed by two colons instead of one.  For
	       example:	 myws::0, big::1, and hydra::0.1.

       An X server can use several types of access control.   Mechanisms  pro-
       vided in	Release	6 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.
	   MIT-KERBEROS-5		 Kerberos Version 5 user-to-user.

       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 manual	page.

       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/

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


       The nodename specifies the name (or decimal numeric address) of the ma-
       chine  on  which	 the font server is running.  The objname is a normal,
       case-insensitive	DECnet object name.   The  cataloguelist  specifies  a
       list of catalogue names,	with '+' as a separator.

       Examples:  DECnet/SRVNOD::FONT$DEFAULT, decnet/44.70::font$special/sym-

       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/lib/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.)  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 identified 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 Tookit 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/lib/X11/,  but this can be overridden with the XFILESEARCH-
	       PATH environment	variable) are searched	for  for  application-
	       specific	resources.  For	example, application default resources
	       are usually kept	in /usr/local/lib/X11/app-defaults/.  See  the
	       X Toolkit Intrinsics - C	Language Interface manual for details.

	       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/lib/X11/locale.

	      This must	point to a file	containing X resources.	The default is
	      $HOME/.Xdefaults-_hostname_.   Unlike    /usr/local/lib/X11/Xre-
	      sources, 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:

		  %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:

		  %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/lib/X11/XKeysymDB.

       XCMSDB This must	point to a color name database file. The default value
	      is usr/local/lib/X11/Xcms.txt.

	      This must	point to a configuration file for the Xft library. The
	      default value is /usr/local/lib/X11/XftConfig.

	      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 the application should connect.  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 $*
	   %  xon filesysmachine xload

       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/lib/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 StringConversionsWarning 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), Xprint(7), appres(1),
       bdftopcf(1),  bitmap(1),	 editres(1),  fsinfo(1),   fslsfonts(1),   fs-
       tobdf(1),   iceauth(1),	imake(1),  lbxproxy(1),	 kbd_mode(1),  makede-
       pend(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),  xdpyinfo(1),
       xfd(1), xfindproxy(1), xfs(1), xfwp(1), xhost(1), xinit(1), xkbbell(1),
       xkbcomp(1), xkbevd(1), xkbprint(1), xkbvleds(1),	xkbwatch(1), xkill(1),
       xlogo(1),  xlsatoms(1),	xlsclients(1),	xlsfonts(1),  xmag(1), xmh(1),
       xmodmap(1), xon(1), xplsprinters(1),  xprop(1),	xrdb(1),  xrefresh(1),
       xrx(1),	xset(1),  xsetroot(1),	xsm(1),	xstdcmap(1), xterm(1), xwd(1),
       xwininfo(1),  xwud(1).	Xserver(1),   Xdec(1),	 Xdmx(1),   XmacII(1),
       Xsun(1),	 Xnest(1),  Xvfb(1),  Xorg(1),	XDarwin(1), Xprt(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, LLC. The names of all people who made it a
       reality 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.

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