Editing Xterm (section)

==Features==

===Terminal emulation===
Early versions emulated the [[VT102]] and [[Tektronix 4014]].  <ref>{{cite web|url=https://invisible-island.net/xterm/xterm.faq.html#what_is_it|title=What is XTerm?|author=Thomas E. Dickey|access-date=2018-06-04|archive-url=https://web.archive.org/web/20180624104926/https://invisible-island.net/xterm/xterm.faq.html#what_is_it|archive-date=2018-06-24|url-status=live}}</ref>

Later versions added control sequences for [[Digital Equipment Corporation|DEC]] and other terminals such as:
* [[VT220]]: Added in patch 24.<ref name=p24>{{Cite web|url=https://invisible-island.net/xterm/xterm.log.html#xterm_24 |title=Patch #24 - 1996/8/11 - XFree86 3.1.2Ee |access-date=2008-02-25 |archive-url=https://web.archive.org/web/20011222194057/http://invisible-island.net/xterm/xterm.log.html#xterm_24 |archive-date=2001-12-22 |url-status=live}}</ref> Later, in 1998, xterm added support for VT220 features, such as extending its support of [[ISO-2022]] [[ISO-2022#Shift functions|''shift functions'']] to provide the [[National Replacement Character Set]] feature.
* [[VT320]]: Added in patch 24.<ref name=p24 />
* [[VT420]]: DECSTR (soft terminal reset) was added in patch 34.<ref name=p34>{{Cite web |url=https://invisible-island.net/xterm/xterm.log.html#xterm_34 |title=Patch #34 - 1997/1/5 - XFree86 3.2o |access-date=2008-02-25 |archive-url=https://web.archive.org/web/20011222194057/http://invisible-island.net/xterm/xterm.log.html#xterm_34 |archive-date=2001-12-22 |url-status=live }}</ref>    In 2012, xterm's default emulation was changed to [[VT420]] to allow [[tmux]] to assume the corresponding left/right margin support.<ref name=p280>{{Cite web|url=https://invisible-island.net/xterm/xterm.log.html#xterm_280 |title=Patch #280 - 2012/06/24 |access-date=2021-12-21 |archive-url=https://web.archive.org/web/20120926050154/https://invisible-island.net/xterm/xterm.log.html#xterm_280 |archive-date=2012-09-26 |url-status=live}}</ref>
* [[VT520]]: Although not officially emulated, parts of VT520 features were implemented.<ref>{{Cite web |url=https://invisible-island.net/xterm/xterm.faq.html#why_not_vt520 |title=Why not emulate VT520? |access-date=2007-01-06 |archive-url=https://web.archive.org/web/20120325084746/http://invisible-island.net/xterm/xterm.faq.html#why_not_vt520 |archive-date=2012-03-25 |url-status=live }}</ref> Controls DECSMBV and DECSWBV for setting the margin- and warning-bell volume were added in patch 254.<ref name=p254>{{Cite web |url=https://invisible-island.net/xterm/xterm.log.html#xterm_254 |title=Patch #254 - 2010/1/6 |access-date=2021-12-21 |archive-url=https://web.archive.org/web/20110412000243/http://invisible-island.net/xterm/xterm.log.html#xterm_254 |archive-date=2011-04-12 |url-status=live }}</ref>

===Customization===
[[Image:XtermMenus.png|thumb|right|Example showing xterm's toolbar.]]
[[Image:Xterm-256color.svg|thumb|right|Chart of the 256 colors available in an xterm with color support. XTerm color numbers and [[RGB]] values are shown for each. (Updated 2024)]]
As with most [[X Window System|X]] applications, xterm can be customized via global [[X resources]] files (e.g. /usr/lib/X11/app-defaults/XTerm), per-user resource files (e.g. ~/XTerm, ~/.Xresources), or [[command-line argument]]s. Most of the command-line options correspond to resource settings, as noted in the manual page.

While the name of the program is ''xterm'', the X resource class is ''XTerm''. The '''uxterm''' script overrides this, using the ''UXTerm'' resource class.

XTerm normally does not have a menu bar. To access xterm's three menus, users hold the control key and press the left, middle, or right mouse button. Support for a "toolbar" can be compiled-in, which invokes the same menus.

===Protocols===
Supported terminal control functions include:
* [[ANSI X3.64]]
* [[Sixel]]
* Digital Equipment Corporation VT family:
** [[VT52]]
** [[VT102]]
** [[VT220]]
** [[VT420]]
* Tektronix family:
** [[Tektronix 4014]]

In addition to protocols used in commercially available terminal machines, xterm added a few protocols that have been adopted by other terminal emulators, such as:
* Mouse tracking: Support for buttons 4 and 5 was added in patch 120.<ref name=p120>{{Cite web|url=https://invisible-island.net/xterm/xterm.log.html#xterm_120 |title=Patch #120 - 1999/10/28 - XFree86 3.9.16c}}</ref>
* 16-color terminal protocol: Added in patch 39.<ref name=p39>{{Cite web|url=https://invisible-island.net/xterm/xterm.log.html#xterm_39 |title=Patch #39 - 1997/5/24 - XFree86 3.2Xl}}</ref>
* [[256 colors]] terminal protocol: Added in patch 111.<ref name=p111>{{Cite web|url=https://invisible-island.net/xterm/xterm.log.html#xterm_111 |title=Patch #111 - 1999/7/10 - XFree86 3.9Pw}}</ref>
* 88-color terminal protocol: Added in patch 115.<ref name=p115>{{Cite web|url=https://invisible-island.net/xterm/xterm.log.html#xterm_115 |title=Patch #115 - 1999/9/18 - XFree86 3.9.16a}}</ref>
* Custom color palette: Ability to specifying the RGB values for palette entries was added in patch 111.<ref name=p111 />
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=== Fonts ===
Initially Xterm supported only [[Portable Compiled Format]] (PCF) [[bitmap font]] until 2000 when [[Xft]] library was introduced to support modern [[Computer font|stroke-based fonts]] like [[TrueType]].<ref>{{Cite web |title=XTERM - Change Log |url=https://invisible-island.net/xterm/xterm.log.html#xterm_148 |access-date=2022-11-17 |website=invisible-island.net}}</ref>