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Xterm

xterm is the standard terminal emulator for the X Window System. It is highly configurable and has many useful and some unusual features.

The ultimate authorities for using and customizing xterm are the man pages for xterm, uxterm, koi8rxterm, and resize; and the XTerm ChangeLog.

Basics

Xterm is used with different hardware on a variety of operating systems, not just with a PC keyboard on a GNU/Linux system. There are several options you can set in your X resources files that may make this terminal emulator much easier to use.

  • Allow xterm to report the TERM variable correctly. Do not set the TERM variable from your ~/.bashrc or ~/.bash_profile or similar file. The terminal itself should report the correct TERM to the system so that the proper terminfo file will be used. Two usable terminfo files are xterm, and xterm-256color.
– Without setting TERM explicitly, xterm should report $TERM as xterm. You can check this from within xterm using either of these commands:
$ echo $TERM
$ tset -q
– When TERM is not set explicitly, color schemes for some programs, such as vim, may not appear until a key is pressed or some other input occurs. This can be remedied by setting the resource termName, either from the command line with xterm -tn xterm-256color, or by setting the resource value:
xterm*termName: xterm-256color
  • Use UTF-8. First make certain your locale settings are correct for UTF-8, then add this to your resource file so that xterm interprets all incoming data as UTF-8 encoded:
XTerm*locale: true
XTerm*metaSendsEscape: true

Scrolling

As new lines are written to the bottom of the xterm window, older lines disappear from the top. Xterm saves these lines and they can be redisplayed by scrolling. By default, 1024 lines are saved. You can change the number of saved lines with the saveLines resource,

Xterm*saveLines: 4096

Other X resources that affect scrolling are jumpScroll, set to true by default, and multiScroll and fastScroll, both of which default to false.

For manual scrolling, one can use the mouse wheel, or the key combinations Template:Keypress and Template:Keypress to scroll a half page at a time, or one can use the scrollbar.

The Scrollbar

The scrollbar is not shown by default. It can be made visible by a menu selection, by command line options, or by setting resource values. It can be made to appear to the left or right of the window and its visual appearance can be modified through resource settings.

The scrollbar operates differently from what you may be accustomed to using.

  • To scroll down:
– Click on the scrollbar with the left mouse button.
– Click on the scrollbar below the thumb with the middle mouse button.
  • To scroll up:
– Click on the scrollbar with the right mouse button.
– Click on the scrollbar above the thumb with the middle mouse button.
  • To position text, moving in either direction:
– Grab the thumb and use "click-and-drag" with the middle mouse button.

Menus

The Archlinux version of xterm is compiled with the toolbar, or menubar, disabled. The menus are still available as popups when you press Template:Keypress within the xterm window. The actions invoked by the menu items can often be accomplished using command line options or by setting resource values.

Tip: If the popup menu windows show only as small boxes, it is probably because you have a line similar to this, xterm*geometry: 80x32, in your resources file. This does start xterm in an 80 column by 32 row main window, but it also forces the menu windows to be 80 pixels by 32 pixels! Replace the incorrect line with this:
xterm*VT100.geometry: 80x32

Some of the menu options are discussed below.

Main Options Menu

Ctrl + LeftMouse

  • Secure Keyboard attempts to ensure only the xterm window, and no other application, receives your keystrokes. The display changes to reverse video when it is invoked. If the display is not in reverse video, the Secure Keyboard mode is not in effect. Please read the "SECURITY" section of the xterm man page for this option's limitations.
  • Allow SendEvents allows other processes to send keypress and mouse events to the xterm instance. Because of the security risk, do not enable this unless you are very sure you know what you are doing.
  • Log to File – The log file will be named Xterm.log.hostname.yyyy.mm.dd.hh.mm.ss.XXXXXX. This file will contain all the printed output and also all cursor movements. Logging may be a security risk.
  • The six Send *** Signal menu items are not often useful, except when your keyboard fails. HUP, TERM and KILL will close the xterm window. KILL should be avoided, as it does not allow any cleanup code to run.
  • The Quit menu item will also close the xterm window – it is the same as sending a HUP signal. Most users will use the keyboard combination Template:Keypress or will type exit to close an xterm instance.

VT Options Menu

Ctrl + MiddleMouse

  • Select to Clipboard – Normally, selected text is stored in PRIMARY, to be pasted with Template:Keypress or by using the middle mouse button. By toggling this option to on, selected text will use CLIPBOARD, allowing you to paste the text selected in an xterm window into a GUI application using Template:Keypress. The corresponding XTerm resource is selectToClipboard.
  • Show Alternate Screen – When you use an a terminal application such as vim, or less, the alternate screen is opened. The main VT window, now hidden, remains in memory. You can view this main window, but not issue any commands in it, by toggling this menu option. You are able to select and copy text from this main window (when using vim, hold down Template:Keypress while using the mouse) to paste into your editor in the alternate screen. Using the alternate screen may take some trial and error experimentation.
  • Show Tek Window and Switch to Tek Mode – The Tektronix 4014 was a graphics terminal from the 1970s used for CAD and plotting applications. The command line program graph, from plotutils, and the application gnuplot can be made to use xterm's Tek emulation; most people will prefer more modern display options for charting data.