xref: /xsrc/external/mit/xterm/dist/INSTALL

-- $XTermId: INSTALL,v 1.185 2020/09/19 16:53:27 tom Exp $
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Xterm was originally built as part of the X Window System source tree, using
imake to generate a Makefile from Imakefile.

An example Imakefile is provided for legacy use.

The preferred method uses the configure script to generate a Makefile from
Makefile.in

Options:
-------

Autoconf configure scripts recognize two types of application-defined
options, enable/disable and with/without.  The latter, by convention, are
used for denoting inclusion of external packages, while the former denote
enabling/disabling of internal features.  The configure --help option lists
the available options.  This script uses "enable" and "disable" to indicate
the sense of the default behavior.

The options (in alphabetic order):

  --disable-256-color     disable 256-color support

  	Do not compile-in code that interprets SGR 38 and 48 for 256-colors.
	If this feature is disabled, the 88-color feature will be used.

  --disable-88-color      disable 88-color support

	Do not compile-in code that interprets SGR 38 and 48 for 88-colors.
	The 256-color option overrides this.

  --disable-16-color      disable 16-color support

	Do not compile-in code to recognize aixterm-style control sequences
	that support color values 8-15.

	Most color applications know only about 8 ANSI colors, but some
	(e.g., ones built with ncurses) do.

  --disable-active-icon   disable X11R6.3 active-icon feature

	Do not compile-in code to support the active-icon feature.  This is
	not configured on systems (e.g., X11R5) which lack the library
	support needed.

	Xterms with an active icon continue to respond to input and update
	their display when iconified.  Not all window managers support
	active icons.  Those that do include fvwm, olvwm and mwm.

  --disable-ansi-color    disable ANSI color

  	Do not compile-in code for ANSI colors.

  --disable-blink-cursor  disable support for blinking cursor

	Do not compile-in code that implements a blinking cursor.  The blinking
	cursor is enabled either by resource setting or by popup menu entry.

  --disable-bold-color    disable PC-style mapping of bold colors

	Do not compile-in code that maps colors 8-15 to bold versions of
	colors 0-7.

	Some applications have hardcoded logic that assumes this.  It does
	not interfere with the 16-color support.

  --disable-boxchars      disable fallback-support for box chars

  	Do not compile-in code to generate approximations for box/graphic
	characters.

	Most fonts do not contain the vt100-style graphic characters in
	positions 0-31.  Many applications use the line-drawing characters,
	e.g., to make boxes.  When xterm loads a font, it checks if those
	characters are present, and draws its own if they are missing.

  --disable-broken-st     disallow broken string-terminators,

	Do not compile-in code that works around a bug in some ISDN routers
	(and possibly other applications written by the same people):  they
	send an unterminated control string in their banner text, making xterm
	freeze.

	The workaround tells xterm to stop processing the control string when
	it receives one of the whitespace control characters such as newline.
	That was the behavior before patch #171.

	See also --enable-broken-osc

  --disable-c1-print      disallow -k8 option for printable 128-159,

	Use this option to suppress support for nonstandard use of codes
	128-159, which normally are considered control characters.  Some users
	have fonts which use those positions.  The default value for the
	allowC1Printable resource is false, so this feature does not impact
	normal users.

  --disable-color-class   disable color class resources

	Use this option to change most of the color resources to use Foreground
	as the color class.  This is the older (before patch #157) behavior
	which has the drawback that setting the Foreground resource on most
	platforms prevents use of color since the class is evaluated before
	the instance.

  --disable-color-mode    disable default colorMode resource

  	Do not compile-in code that sets the default value of the colorMode
	resource to ``true''.

  --disable-desktop       disable install of xterm desktop files

	Do not install the xterm desktop files, used in menus.
	These use the icons installed in the --with-icondir option.
	Use the environment variable $DESKTOP_FLAGS to supply options
	required by desktop-file-install.

	Note: If desktop-utils is not found they will not be installed anyway.

  --disable-direct-color  disable direct color support

  	Do not compile-in code that interprets SGR 38 and 48 for direct colors.
	This feature extends the 256-color feature.

  --disable-doublechars   disable support for double-size chars

  	Do not compile-in code that supports font-manipulation needed to
	implement vt100-style double-sized characters.

  --disable-echo          test: display "compiling" commands

  	Modify the generated Makefile so that most compiler options are
	not shown.  This makes it simpler to read a build log and see the
	actual warning messages.

  --disable-fifo-lines    enable FIFO-storage for saved-lines

	With patch #244, xterm by default stores saved-lines in a FIFO
	(circular buffer), which improves performance when the number of saved
	lines is large.  Disable this option to revert to the pre-244 layout.

  --disable-freetype      disable freetype library-support

	Do not use freetype libraries if they are found.  Normally they will
	be used automatically.

  --disable-full-tgetent  disable check for termcap library

  	Do not look for the tgetent() function specifically in the termcap
	library, accept the first library (from termlib, ncurses and curses)
	which contains this function rather than continuing to search for
	a termcap implementation rather than terminfo.  The former would
	supply the complete $TERMCAP data needed for some legacy programs.

  --disable-highlighting  disable support for color highlighting

  	Do not compile-in code that allows the selected region to be a
	different color than the reverse of foreground/background colors.

	See the discussion of highlightColor in the manual.

  --disable-i18n          disable internationalization

  	Do not compile-in code to handle multi-byte characters.  This is
	related to, but not identical with the input method logic.

  --disable-imake         disable use of imake for definitions

  	Do not attempt to use imake to determine compiler options.

	The main.c file has many ifdef's which rely on obscure combinations
	known only to imake.  The configure script implements only a
	portion of the tests needed to supplant imake.

  --disable-initial-erase disable setup for stty erase

	Do not compile-in code which aligns the stty erase and the backarrow
	key.  When compiled-in, xterm will optionally use the pty's sense
	of stty erase and apply that to the backarrow mode (sending 8 or 127),
	or go the other way, setting stty erase to match xterm's configuration.

  --disable-input-method  disable input-method

	Do not compile-in code for "input method".  This is an X11R6
	feature which deals with translation of composite characters.

	Some users report problems with their configuration, e.g., messages
	stating that there is no input method defined for the given preedit
	type.  If you do not need input method (and are troubled by the
	warning messages), it is safe to disable this option.

  --disable-leaks         test: free permanent memory, analyze leaks

  	Compile-in code which frees memory which might confuse a leak-testing
	tool.  Normally these chunks of memory are retained as long as xterm
	is running.

  --disable-luit          disable support for luit filter (Unicode translation)

	Luit is a filter that can be run between an arbitrary application and a
	UTF-8 terminal emulator.  It will convert application output from the
	locale's encoding into UTF-8, and convert terminal input from UTF-8
	into the locale's encoding.

	This is normally enabled, relying upon "--enable-wide-chars".

  --disable-maximize      disable actions for iconify/deiconify/maximize/restore

	Do not compile-in code that implements runtime 'actions' for
	iconifying, maximizing, etc.

	Most users will find that the window manager is more suitable for
	this sort of manipulation than putting the capabilities into xterm.

  --disable-num-lock      disable NumLock keypad support

	Do not compile-in code that looks for the actual NumLock key to
	support vt100/vt220 keypad translation.

	This is used in xterm to simplify logic, and to workaround some
	quirks of the keyboard tables.  Use the ``numLock'' resource to
	disable this feature if you must customize xterm in some other way.

	(The same ifdef controls the metaSendsEscape support).

  --disable-openpty       disable openpty, prefer other interfaces

	Do not check for, or use openpty().  Instead, use other interfaces such
	as posix_openpt().  Modern (sic) BSD systems should have a workable
	openpty() interface.  Older systems may not.

  --disable-paste64       disable support for bracketed paste mode

	Do not compile-in code to support bracketed paste mode, along with
	functions for setting/getting the selection data, termed "paste64".

	(see ctlseqs.ms description of OSC 52, and DECSET 2004).

  --disable-print-graphics disable screen dump to sixel support

	Do not compile-in code to support screen-dumps for ReGIS graphics.

  --disable-pty-handshake disable support for pty handshakes

	This feature is used to ensure that the child process's terminal modes
	match the parent's.  In particular, it addresses a problem where the
	terminal size is not defined in the stty settings.

  --disable-rectangles    disable VT420 rectangle support

	Do not compile-in code to support VT420 rectangle control-sequences.

  --disable-regex         disable regular-expression selections

	Do not compile-in code to support the "regex" option for multiple
	mouse clicks.

  --disable-rightbar      disable right-scrollbar support

  	Do not compile-in code that supports a scrollbar on the right.

	Left/right scrollbars are a matter of taste.  Some older libraries
	(e.g., X11R5) do not perform the geometry computation correctly,
	leaving the right scrollbar incorrectly positioned after changing
	the font size.

  --disable-rpath-hack    don't add rpath options for additional libraries

	By default, the configure script looks for libraries in unusual places
	and adds an rpath linker option to help.

  --disable-samename      disable check for redundant name-change

	Do not compile-in code that suppresses redundant updates to the
	titlebar when the text has not changed.

  --disable-screen-dumps  disable XHTML and SVG screen dumps

	Do not compile-in code that provides XHTML and SVG screen dumps.

  --disable-selection-ops disable selection operations

	Do not compile-in code to support the actions which allow users
	to bind keys that use the selection or extract data from the screen.

  --disable-session-mgt   enable support for session management

	Do not compile-in code which adds simple session management hooks
	which are used when closing an xterm.  Normally the code is
	compiled-in, except for systems which do not support it.

  --disable-setgid        disable setgid

	Do not install xterm using setuid/setgid permissions.  Drop setgid
	permissions on startup.

  --disable-setuid        disable setuid

	Do not install xterm using setuid/setgid permissions.  Drop setuid
	permissions on startup.

  --disable-sixel-graphics disable support for sixel-graphics

  	Do not compile-in code to support sixel-graphics

  --disable-sun-fkeys

  	Do not compile-in code to support Sun-style function keys.

  --disable-tcap-fkeys    disable termcap function-keys

	Do not compile-in code to support feature which allows xterm to use the
	function-key definitions from the termcap/terminfo entry which it used
	to set the $TERM variable on startup.

  --disable-tcap-query    disable termcap query/report

	Do not compile-in code to support DCS '+' control sequence, which
	allows an application to ask xterm what control sequences it would
	transmit for specified function keys, given the termcap or terminfo
	names.

  --disable-tek4014       disable tek4014 emulation

  	Do not compile-in code to support Tektronix 4014 emulation.

	This reduces the executable size by 17% (checked 1999/3/13).

	Some people use the Tektronix emulation (which has been in xterm
	for many years) as an example of code bloat, though this is not an
	accurate impression.

  --disable-vt52          disable VT52 emulation

  	Do not compile-in code to support vt52 emulation.

	A genuine vt100 emulates a vt52.

  --disable-wide-attrs    disable wide-attribute support

	Xterm's base attributes include all of those used in DEC terminals.
	ISO 6429 defines a few more which historically have found little use.
	Some people find these amusing.

	This is normally enabled.  The direct-colors feature relies upon it.

  --disable-wide-chars    disable wide-character support

  	The wide-character code supports Unicode and UTF-8.

	This is normally enabled.

  --disable-ziconbeep     disable -ziconbeep option

	Do not compile-in code that modifies the icon's title and sounds a
	beep when they receive output.

  --enable-16bit-chars    enable 16-bit characters support

	Enable wide-character support, but store only 16-bits for each wide
	character.  Unicode values can be larger than 16-bits, up to 21-bits.
	This uses less memory, but is less complete.  However, most languages
	are covered by the 16-bit encoding.

  --enable-alt-sends-esc  set default altSendsEscape resource (default: no)

	This sets the default resource value, which is shown in the manpage.

  --enable-backarrow-key  set default backarrowKey resource (default: true)

	This sets the default resource value, which is shown in the manpage.

  --enable-backarrow-is-erase set default backarrowKeyIsErase resource (default: false)

	This sets the default resource value, which is shown in the manpage.

  --enable-broken-osc     allow broken Linux OSC-strings

	Compile-in code to accommodate scripts that write Linux's malformed
	palette control strings without checking.  The result makes xterm
	appear to freeze.  This workaround makes xterm ignore the strings,
	and is compiled-in by default for Linux.

  --enable-builtin-xpms   compile-in icon data

	Compile-in X pixmap data for these icons:
		filled-xterm
		mini.xterm
		xterm-color
		xterm
	at these sizes
		16x16
		32x32
		48x48

  --enable-dabbrev        enable dynamic-abbreviation support

	Compile-in support for "dabbrev-expand()" action and related key
	translation.

  --enable-dec-locator    enable DECterm Locator support
	Add support for DEC Locator control sequences for xterm:

		DECEFR - Enable Filter Rectangle
	        DECELR - Enable Locator Reports
		DECSLE - Select Locator Events
		DECRQLP - Request Locator Position

	This allows the xterm mouse to be used with applications that use the
	DEC Locator sequences, such as VAX Tpu, or SMG$ based applications.

  --enable-delete-is-del  set default deleteIsDEL resource (default: maybe)

	This sets the default resource value, which is shown in the manpage.

  --enable-double-buffer  enable double-buffering

	Set the initial value of the "buffered" resource, which tells
	xterm to use double-buffering for display to reduce flicker.

  --enable-env-terminfo   setenv $TERMINFO if --with-own-terminfo gives value

	Use the custom terminfo directory specified in "--with-own-terminfo"
	as the $TERMINFO variable for the shells spawned by xterm.  Setting
	this variable makes most curses (and termcap) applications look in
	that directory for terminal descriptions.

  --enable-exec-xterm     enable "spawn-new-terminal" action

  	If your platform supports the process filesystem "cwd" link,
	compile-in support for the "spawn-new-terminal" action, which
	allows you to define a key translation that runs a new xterm
	using the same working directory as the current process within
	xterm.

  --enable-hp-fkeys       enable support for HP-style function keys

  	Compile-in code to support HP-style function keys.

  --enable-load-vt-fonts  enable load-vt-fonts() action

  	Compile-in code that allows user to define load different VT-font
	definitions at runtime.

  --enable-logfile-exec   enable exec'd logfile filter

  	Compile-in code that allows logging piped via an external filter.

  --enable-logging        enable logging

  	Compile-in code that allows logging.

	Logging was disabled in X11R5 xterm because of security problems.
	They were addressed in X11R6, but the feature was not reinstated
	because of concerns (long past) about xterm running as root-setuid.

  --enable-meta-sends-esc set default metaSendsEscape resource (default: no)

	This sets the default resource value, which is shown in the manpage.

  --enable-mini-luit      enable support for poor man's luit filter (Latin-9)

	Provide built-in support for Latin-9, relying on having specified
	Unicode (ISO10646) fonts and setting the locale resource to "checkfont".

	This sets "--enable-luit" as a side-effect.

  --enable-narrowproto    enable narrow prototypes for X libraries

	Originally xterm was built using imake rather than a configure script.
	One feature of imake that is not possible to guess within the
	configure script is the wide-prototype compile-time definition
	NARROWPROTO.  When this is not set properly, the Athena widget
	scrollbars do not work properly.  xterm's configure script has a
	fallback case which allows disabling imake.  However, this is moot
	with the X.org "modular" build, whose compiler options are unrelated to
	imake or older versions of any libraries that it may distribute.  In
	this case, the configure script needs some help.  Use this option to
	enable or disable NARROW proto (and disable imake with the
	--disable-imake option) to match the whims of X.org hackers.

	For instance

		configure --disable-imake --disable-narrowproto

  --enable-pty-erase      set default ptyInitialErase resource (default: false)

	This sets the default resource value, which is shown in the manpage.

  --enable-readline-mouse enable support for mouse in readline applications

	Compile-in code to support predecessor to bracketed paste mode, i.e.,
	provide functions for setting/getting the selection data.  Essentially
	this puts xterm into a mode that sends special function-key strings to
	bracket the data.

	(The "paste64" feature, which fits xterm's protocol better, is
	configured by default).

  --enable-sco-fkeys      enable support for SCO-style function keys

  	Compile-in code to support SCO-style function keys.

  --enable-regis-graphics enable support for ReGIS graphics

  	Compile-in code to support experimental ReGIS graphics

  --enable-toolbar        enable pulldown menus on toolbar

  	Compile-in code that builds a toolbar with pulldown menus.  The
	normal popup menus are still available.

	This is an experimental option.  As of patch #206, it is known to
	work well with fvwm, but not as well with some other window managers,
	e.g., KDE's Kwin and IceWM.

	In addition to isolated layout problems, it is reported that some
	flavors of the Athena widget library perform badly with ISO-10646
	fonts.  You can work around those by setting the menu fonts to
	an ISO-8859 variant in your X resources.

  --enable-trace          test: set to enable debugging traces

  	Compile-in code to trace xterm's internal states.

	This is a debugging feature.  It causes xterm to produce two files
	(Trace-parent.out and Trace-child.out).

  --enable-warnings       test: turn on GCC compiler warnings

	Modify the generate Makefile to turn on gcc compiler warnings.

	I use this option regularly, and correct all but a few (difficult)
	problems.

  --enable-xmc-glitch     test: enable xmc magic-cookie emulation

  	Compile-in code that simulates the terminfo "magic cookie" glitch.

	This is for testing ncurses.

  --with-Xaw3d            link with Xaw 3d library

  	Look for, compile and link with the Xaw 3d widget library.

  --with-Xaw3dxft         link with Xaw 3d xft library

	Look for, compile and link with the Xaw 3d xft widget library.

  --with-XawPlus          link with Athena-Plus library

  	Look for, compile and link with the Xaw Plus widget library.

  --with-app-class=XXX    X resource class (default: XTerm)

	Rename the X resource class, e.g., for packaging a development version
	of xterm with different result names.

  --with-app-defaults=DIR directory in which to install resource files (default: EPREFIX/lib/X11/app-defaults)

	autoconf scripts assume that all of the files should be installed
	under the same top-level directory.  But X applications defaults
	must be installed into a special directory, e.g.,

		/usr/X11/lib/app-defaults

	However, there is no standard for this pathname.  The manual page
	for X notes that the environment variable $XUSERFILESEARCHPATH can
	specify a list of places where X searches for applications defaults.
	Also, it may look in $XAPPLRESDIR, but that usually is not related
	to where xterm might be installed.  To keep it simple, the configure
	script uses

		EPREFIX/lib/X11/app-defaults

	as the default (EPREFIX is --prefix).  That makes it work normally
	for most systems if --prefix is /usr.  For other installs, e.g., to
	/usr/local, you should use this option to customize the location to
	match your system configuration.

	Use --with-app-defaults=auto to ask the configure script to look in
	a list of well-known locations for an existing directory.

	Use --without-app-defaults or --with-app-defaults=no to disable the
	feature.

  --with-dmalloc          test: use Gray Watson's dmalloc library

	Check for and link with dmalloc.

  --with-dbmalloc         test: use Conor Cahill's dbmalloc library

	Check for and link with dbmalloc.

  --with-desktop-category=XXX  one or more desktop categories or auto
	This is a list of names.  The configure script maps blanks and commas
	to semicolons (";") which are used by the desktop utilities as a
	separator.

	The default value "auto" tells the configure script to look
	at existing ".desktop" files for xterm and common terminal
	emulators, to use those.  If none are found, the script uses this
	default:
		System;TerminalEmulator;

  --with-freetype-config  configure script to use for FreeType

	Use a specific option value to tell the configure script to try
	just one of the variations:

	"pkg*", e.g., pkg-config or pkgconfig uses whatever pkg-config
		script was found.

	otherwise, the parameter value is used as the name of the script
	to try, using --cflags and --libs options.

	Use --without-freetype-config to enable the --with-freetype-cflags
	and --with-freetype-libs options.

	The default value "auto" tells the configure script to try the
	pkg-config script first, then freetype-config and finally xft-config.

  --with-freetype-cflags  -D/-I options for compiling with FreeType library

	Override options provided by xft-config or freetype-config.

  --with-freetype-libs    -L/-l options for linking with FreeType library

	Override options provided by xft-config or freetype-config.

  --with-icon-name=NAME override icon name (default: xterm-color)

	xterm comes with a choice of icons:

	xterm-color: depicts a conventional terminal image, and is the default
		icon used for icon-themes.

	mini.xterm: a more iconic choice which is readily identifiable at
		small sizes.  This is used for window decoration, e.g., the
		icon at the upper left corner in many window managers.

  --with-icon-symlink=NAME create symbolic links to icon name (default: NONE)

	This is a workaround for certain systems which translate icon names
	containing "xterm", e.g., "xterm-color" into the single icon "xterm".
	The option should also be harmless on a properly configured system.

	If the option is used, its default value is "xterm".  For each icon,
	the makefile will strip the suffix (e.g., ".png"), as well as the part
	of the filename which denotes the size (e.g., "_32x32" in an xpm file),
	and constructs a link with that name to the icon.

	If the option is unused, its default value is "NONE" (no link is made).

  --with-icondir=DIR directory in which to install icon files (default: no)

	The X libraries may automatically search these locations:

	$HOME/.icons
	$XDG_DATA_DIRS/icons
	/usr/share/pixmaps

	Alternatively, the last may be actually
	/usr/X11R6/share/pixmaps

	Use --with-icondir=auto to tell the configure script to search for
	an existing directory from its list of well-known system locations.

	See also
	http://standards.freedesktop.org/icon-theme-spec/icon-theme-spec-latest.html
	http://www.freedesktop.org/software/icon-theme/

	By default, the option is disabled; it is useful only for the
	--with-icon-theme option.

  --with-icon-theme=XXX   install icons into desktop theme (hicolor)

	Install png and svg icons into the given desktop theme and customize
	the .desktop files to use that theme.  If no theme name is given,
	the default is "hicolor".  If this option is not given, the desktop
	file will use the pixmap files.

  --with-man2html[=XXX]   use XXX rather than groff

	Specify an alternative program to use for converting manpages and
	control sequences document to html.  The default value for the option
	is "man2html".  If the "man2html" script is not found, then "groff" is
	used with groff's special options.

	The "man2html" script reads formatted nroff output from its standard
	input, and writes html to its standard output.  Other input/output
	conventions are not currently supported.

	See
		http://invisible-island.net/scripts
		http://invisible-island.net/scripts/man2html.html

	for an up-to-date version of "man2html".

  --with-neXtaw           link with neXT Athena library

  	Look for, compile and link with the neXT Athena widget library.

  --with-own-terminfo=P   set default $TERMINFO (default: from environment)

  	Modify the generated Makefile to set the target for the 'install-ti'
	rule to point to the given directory.

	If you have the $TERMINFO variable defined in your environment, the
	configure script may use that value, if it matches an existing
	directory.  If no option and no variable are are given, the configure
	script uses /usr/lib/terminfo, if it exists.

	You do not have to run "make install-ti", if there is already a
	workable terminfo description.  Be advised, however, that the
	common variety of "xterm-color" is not suited for xterm, but is
	directed to other variations (such as nxterm) which do not
	support the background-color erase capability.

  --with-pixmapdir=DIR    directory in which to install pixmaps (DATADIR/pixmaps)

	Specify directory in which to install ".xpm" files.

  --with-pcre             use PCRE for regular-expressions

	If regular expressions are not disabled (--disable-regex), use PCRE
	rather than the POSIX regular expressions.

  --with-pcre2            use PCRE2 for regular-expressions

	If regular expressions are not disabled (--disable-regex), use PCRE2
	rather than the POSIX regular expressions.

  --with-pkg-config{=path} enable/disable use of pkg-config

	The configure script looks for certain libraries which have well
	established pkg-config scripts, and will use those settings if
	available.  Not all pkg-config scripts work; this option suppresses
	the check and relies on normal library search paths.

  --with-reference=XXX    program to use as permissions-reference

	To install xterm with setuid permissions, the scripts usually compare
	it with a previous install.  That works well for individual
	maintainers, but can be a problem for packagers who may be
	cross-compiling, etc.  This option lets the package builder specify
	the file used for permissions reference.

  --with-setuid=XXX       use the given setuid user

	Install xterm setuid'd to the given user.  If no parameter value
	is given, assume it is root.

	See also --with-utmp-setgid and --with-utempter, which manipulate
	the setgid group.

  --with-tty-group=XXX    use XXX for the tty-group

	If xterm is installed setuid'd to root, change the group of the tty
	device to the given value on startup.  Three cases are possible:

	a) If this option is not given, the configure script will attempt to
	   find a suitable value (usually "tty"), and verify that it exists in
	   the group database.

	b) If the option value is given, it will use the value even if it does
	   not exist in the group database (allowing packagers to work about
	   deficient environments).

	c) If the option is disabled, e.g., --without-tty-group, the
	   permissions change will use the group-id of the process.

	If xterm is not installed setuid'd to root, this option is not needed,
	since it cannot change the tty device's ownership.

  --with-valgrind         test: use valgrind

	Activate the --disable-leaks option, and ensure that "-g" is added to
	CFLAGS.

  --without-xinerama      do not use Xinerama extension for multiple screens

	Xinerama is an X server extension that allows multiple physical
	screens to behave as a single screen.  If you do not need the feature
	(or do not want the extra library dependency), use this option to
	suppress it.

  --with-xpm=DIR          use Xpm library for colored icon, may specify path

	Use Xpm library to show colored icon in window decoration, e.g.,
	title area.

	Use --without-xpm to suppress this feature.

  --with-xterm-symlink=XXX  make symbolic link to installed xterm

	If any of the configure options to modify the program name i.e.,
	--program-prefix, --program-suffix or --program-transform-name
	are given, this option allows the makefile to create a symbolic link,
	e.g., to "xterm" on install.  The option value gives the name for
	the link, which defaults to "xterm".

	Use --without-xterm-symlink to disable a link to "xterm" if none
	is wanted.

	Corresponding links are also made for "resize", "uxterm" and
	"koi8rxterm", as well as the xterm manpage.

  --with-terminal-id[=V]  set default decTerminalID (default: vt100)

  	Set the default emulation level.

	DEC terminals vt52/vt100/vt220/etc form a series where succeeding
	models emulate features of the older terminals.  While most
	features of these terminals are recognized by xterm at all levels,
	a few behave differently according to the emulation level.

	You can always override this with the command-line option "-ti".

  --with-terminal-type=T  set default $TERM (default: xterm)

	Set the default value for $TERM.  Xterm supports legacy termcap
	applications by constructing a modified version of the $TERMCAP
	variable at initialization, which supplies the resulting screen
	size.  It also sets $TERM, if not already set, for use by programs
	running within xterm.

	The default value "xterm", can be overridden to avoid conflict
	with older versions of xterm, e.g., those that do not implement
	vt220 emulation.

	You can always override this with the command-line option "-tn".

  --with-utempter         use utempter library for access to utmp

	The utempter library is a set-uid wrapper for the utmp facility.
	On systems with Unix98 pty's, xterm can use this library when
	available so it need not be installed set-uid.

  --with-utmp-setgid=XXX  use setgid for access to utmp

	The option value specifies a group to use when installing.
	xterm will be installed with setgid privilege to this group.
	At runtime, xterm will drop the setuid privilege immediately
	after opening the pseudo-terminal, and will have only the
	group privilege needed to access the utmp file.  This relies
	on having POSIX setuid behavior.

-- vile:txtmode