Xterm what is

Several people had made modifications to xterm to support color, but none except for the completely independent rxvt implemented background color erase. Completely mystifying. Being bogged down in ncurses, I didn't get involved in xterm until the very end of , after working on atac. I implemented a workable version of colorized xterm just at the point where XFree86 3.

As luck would have it, they'd incorporated the "old" color model. So I joined the XFree86 project to fix it. As I learned more about xterm , I realized that it implemented part of VT i.

Since a number of people on the Internet are looking for a good VT emulator, it seemed a natural follow-on project to make xterm a good VT emulator. By the release of XFree86 3. Specifies comma-separated lists of character class bindings of the form [ low- ] high: value. These are used in determining which sets of characters should be treated the same when doing cut and paste. See the Character Classes section. Specifies whether xterm should follow the traditional East Asian width convention.

You may have to set this option to " true " if you have some old East Asian terminal based programs that assume that line-drawing characters have a column width of 2. If this resource is " false ", the mkWidth resource controls the choice between the system's wcwidth and xterm 's built-in tables. These specify the colors for the ISO extension. The defaults are, respectively, black, red3, green3, yellow3, a customizable dark blue, magenta3, cyan3, and gray The default shades of color are chosen to allow the colors 8 - 15 to be used as brighter versions.

These specify the colors for the ISO extension if the bold attribute is also enabled. The default resource values are respectively, gray30, red, green, yellow, a customizable light blue, magenta, cyan, and white. These specify the colors for the color extension. The default resource values are for colors 16 through to make a 6x6x6 color cube, and colors through to make a grayscale ramp.

Resources past color15 are available as a compile-time option. Due to a hardcoded limit in the X libraries on the total number of resources to , the resources for colors are omitted when wide-character support and luit are enabled. Besides inconsistent behavior if only part of the resources were allowed, determining the exact cutoff is difficult, and the X libraries tend to crash if the number of resources exceeds the limit. The color palette is still initialized to the same default values, and can be modified via control sequences.

On the other hand, the resource limit does permit including the entire range for colors. If not, these are displayed only when no ANSI colors have been set for the corresponding position.

This specifies the color to use to display bold characters if the " colorBDMode " resource is enabled. Specifies whether characters with the bold attribute should be displayed in color or as bold characters. Note that setting colorMode off disables all colors, including bold. This specifies the color to use to display blink characters if the " colorBLMode " resource is enabled. Specifies whether characters with the blink attribute should be displayed in color.

Note that setting colorMode off disables all colors, including this. This specifies the color to use to display reverse characters if the " colorRVMode " resource is enabled. Specifies whether characters with the reverse attribute should be displayed in color. This specifies the color to use to display underlined characters if the " colorULMode " resource is enabled. Specifies whether characters with the underline attribute should be displayed in color or as underlined characters.

Note that setting colorMode off disables all colors, including underlining. Specifies the number of wide-characters which can be stored in a cell to overstrike combine with the base character of the cell. This can be set to values in the range 0 to 4. In VT keyboard mode see sunKeyboard resource , specifies the amount by which to shift F1-F12 given a control modifier Ctrl.

The default is "10", which means that Ctrl F1 generates the key symbol for F Specifies whether or not the last column bug in more should be worked around. See the -cu option for details. Specifies the color to use for the text cursor. By default, xterm attempts to keep this color from being the same as the background color, since it draws the cursor by filling the background of a text cell.

The same restriction applies to control sequences which may change this color. Setting this resource overrides most of xterm 's adjustments to cursor color. It will still use reverse-video to disallow some cases, such as a black cursor on a black background. Specifies the duration of the "off" part of the cursor blink cycle-time in milliseconds. The same timer is used for text blinking. Specifies the duration of the "on" part of the cursor blink cycle-time, in milliseconds.

If " false ", triple clicking to select a line does not include the Newline at the end of the line. If " true ", the Newline is selected. If " false ", triple clicking to select a line selects only from the current word forward. If " true ", the entire line is selected.

Leading non-digit characters are ignored, e. Specify the character or string which xterm will substitute when pasted text includes a character which cannot be represented in the current encoding. The default is " " a single pound sign.

If the undisplayable text would be double-width, xterm will add a space after the " " character, to give roughly the same layout on the screen as the original text. The default is " false ", for the latter. Specify which features will be disabled if allowColorOps is " false ". This is a comma-separated list of names. The names are listed below.

Specify which features will be disabled if allowFontOps is " false ". The default value is " SetFont,GetFont ". Specify which features will be disabled if allowTcapOps is " false ". The default value is " SetTcap,GetTcap ".

Specify which features will be disabled if allowWindowOps is " false ". This is a comma-separated list of names, or for the controls adapted from dtterm the operation number. Where a number can be used as an alternative, it is given after the name.

Specifies whether or not escape sequences to change colors assigned to different attributes are recognized. Specifies whether or not control sequences sent by the terminal should be eight-bit characters or escape sequences.

If " true ", Meta characters a single-byte character combined with the Meta modifier key input from the keyboard are presented as a single character, modified according to the eightBitMeta resource. If "false", Meta characters are converted into a two-character sequence with the character itself preceded by Esc. The metaSendsEscape and altSendsEscape resources may override this feature.

Generally keyboards do not have a key labeled "Meta", but "Alt" keys are common, and they are conventionally used for "Meta". If they were synonymous, it would have been reasonable to name this resource " altSendsEscape ", reversing its sense.

For more background on this, see the meta function in curses. Note that the Alt key is not necessarily the same as the Meta modifier. X defines modifiers for shift, caps lock and control, as well as 5 additional modifiers that are generally used to configure key modifiers. It also looks for the NumLock key, to recognize the modifier that is associated with that. If your xmodmap configuration uses the same keycodes for Alt- and Meta-keys, xterm will only see the Alt-key definitions, since those are tested before Meta-keys.

NumLock is tested first. It is important to keep these keys distinct; otherwise some of xterm 's functionality is not available. The eightBitInput resource is tested at startup time. If " true ", the xterm tries to put the terminal into 8-bit mode. If " false ", on startup, xterm tries to put the terminal into 7-bit mode. For some configurations this is unsuccessful; failure is ignored. After startup, xterm does not change the terminal between 8-bit and 7-bit mode. As originally implemented in X11, the resource value did not change after startup.

However since patch in xterm can modify eightBitInput after startup via a control sequence. The corresponding terminfo capabilities smm set meta mode and rmm reset meta mode have been recognized by bash for some time. Interestingly enough, bash's notion of "meta mode" differs from the standard definition in the terminfo manual , which describes the change to the eighth bit of a character.

It happens that bash views "meta mode" as the Esc character that xterm puts before a character when a special meta key is pressed. This controls the way xterm modifies the eighth bit of a single-byte key when the eightBitInput resource is set.

The default is "locale". The resource value is a string, evaluated as a boolean after startup. Specifies whether or not eight-bit characters sent from the host should be accepted as is or stripped when printed.

The default is " true ", which means that they are accepted as is. The default is an empty string, i. Specify the pattern for scalable fonts selected from the FreeType library if support for that library was compiled into xterm.

There is no default value. If not specified, or if there is no match for both normal and bold fonts, xterm uses the bitmap font and related resources. It is possible to select suitable bitmap fonts using a script such as this:! Specify a double-width scalable font for cases where an application requires this, e. If the application uses double-wide characters and this resource is not given, xterm will use a scaled version of the font given by faceName. Specify the pointsize for fonts selected from the FreeType library if support for that library was compiled into xterm.

The default is " Although the default is " For example, the "fixed" font usually has a pointsize of "8. If you set faceSize to match the size of the bitmap font, then switching between bitmap and TrueType fonts via the font menu gives comparable sizes for the window.

You can specify the pointsize for TrueType fonts selected with the other size-related menu entries, such as Medium, Huge, etc. If you do not specify a value, they default to "0. If any are not set, xterm uses only the areas of the bitmap fonts. Specifies the name of the normal font. The default is " fixed ".

See the discussion of the locale resource, which describes how this font may be overridden. Modifies the effect of jump scroll jumpScroll by suppressing screen refreshes for the special case when output to the screen has completely shifted the contents off-screen. For instance, cat 'ing a large file to the screen does this. Specifies whether xterm should attempt to use font scaling to draw double-sized characters. Some older font servers cannot do this properly, will return misleading font metrics.

If disabled, xterm will simulate double-sized characters by drawing normal characters with spaces between them. Specify whether xterm should report an error if it fails to load a font: 0. Other fixed-pitch fonts may be more attractive, but lack these glyphs. When using an ISO font and the wideChars resource is true, xterm uses the Unicode glyphs which match the VT line-drawing glyphs. If " false ", xterm checks for missing glyphs in the font and makes line-drawing characters directly as needed.

If " true ", xterm assumes the font does not contain the line-drawing characters, and draws them directly. Specifies whether xterm should use the maximum or minimum glyph width when displaying using a bitmap font. Use the maximum width to help with proportional fonts. The default is " true ", denoting the minimum width. Specifies the color to use for displaying text in the window. Setting the class name instead of the instance name is an easy way to have everything that would normally appear in the text color change color.

Overrides the format of the escape sequence used to report modified keys with the modifyOtherKeys resource. Specifies whether xterm should assume the bounding boxes for normal and bold fonts are compatible. If " false ", xterm compares them and will reject choices of bold fonts that do not match the size of the normal font.

The default is " false ", which means that the comparison is performed. Specifies the preferred size and position of the VT window. Specifies the color to use for the background of selected highlighted text. If not specified i. The default is unspecified: at startup, xterm checks if those resources are set to something other than the default foreground and background colors. Setting this resource disables the check. Specifies whether xterm should reverse the selection foreground and background colors when selecting text with reverse-video attribute.

This applies only to the highlightColor and highlightTextColor resources, e. If " true ", xterm reverses the colors, If " false ", xterm does not reverse colors, The default is " true ". If " false ", selecting with the mouse highlights all positions on the screen between the beginning of the selection and the current position. If " true ", xterm highlights only the positions that contain text that can be selected. Depending on the way your applications write to the screen, there may be trailing blanks on a line.

Erasing the display changes the internal state of each cell so it is not considered a blank for the purpose of selection. Blanks written since the last erase are selectable.

If you do not wish to have trailing blanks in a selection, use the trimSelection resource. Specifies the color to use for the foreground of selected highlighted text. Specifies whether to work around a bug in HP's xdb, which ignores termcap and always sends Esc F to move to the lower left corner. Specifies the border color for the active icon window if this feature is compiled into xterm. Not all window managers will make the icon border visible.

Specifies the border width for the active icon window if this feature is compiled into xterm. Not all window managers will make the border visible. Specifies the font for the miniature active icon window, if this feature is compiled into xterm. The default is " nil2 ". Specifies which of the VT fonts to use initially.

Values are the same as for the set-vt-font action. The default is " d ", i. Specifies the number of pixels between the characters and the window border. Specifies whether characters with the underline attribute should be displayed in an italic font or as underlined characters. It is implemented only for TrueType fonts.

Specifies whether or not jump scroll should be used. See fastScroll for a variation. Specifies whether xterm will keep the selection even after the selected area was touched by some output to the terminal. Specifies the initial keyboard dialect, as well as the default value when the terminal is reset. The value given is the same as the final character in the control sequences which change character sets.

Limits resizing of the screen via control sequence to a given multiple of the display dimensions. The default is " 1 ". Specifies how to use luit , an encoding converter between UTF-8 and locale encodings. The resource value ignoring case may be: true. For other locales, xterm will use conventional 8bit mode. If mini-luit is compiled-in, xterm will check if a Unicode font has been specified.

If so, it checks if the character encoding for the current locale is POSIX, Latin-1 or Latin-9, uses the appropriate mapping to support those with the Unicode font.

For other encodings, xterm assumes that UTF-8 encoding is required. Any other value, e. The actual list of supported encodings depends on luit. The default is " medium ". The help message shown by " xterm -help " lists the default value, which depends on your system configuration. If the encoding converter requires command-line parameters, you can add those after the command, e.

Specifies whether or not the shell to be run in the window should be started as a login shell. Specifies whether or not the bell should be rung when the user types near the right margin. If " true ", Meta characters a character combined with the Meta modifier key are converted into a two-character sequence with the character itself preceded by Esc. This applies as well to function key control sequences, unless xterm sees that Meta is used in your key translations.

If " false ", Meta characters input from the keyboard are handled according to the eightBitInput resource. If mkSampleSize is nonzero, and mkWidth and cjkWidth are false, on startup xterm compares its built-in tables to the system's wide character width data to decide if it will use the system's data.

It tests the first mkSampleSize character values, and allows up to mkSamplePass mismatches before the test fails. The default for the allowed number of mismatches is With mkSamplePass , this specifies a startup test used for initializing wide character width calculations.

The default number of characters to check is Specifies whether xterm should use a built-in version of the wide character width calculation. See also the cjkWidth resource which can override this. Here is a summary of the resources which control the choice of wide character width calculation: cjkWidth: mkWidth: Action: false. Tells how to handle the special case where Control-, Shift-, Alt- or Meta-modifiers are used to add a parameter to the escape sequence returned by a cursor-key.

The default is " 2 ": Set it to -1 to disable it. Set it to 1 to prefix modified sequences with CSI. Set it to 2 to force the modifier to be the second parameter if it would otherwise be the first. Tells how to handle the special case where Control-, Shift-, Alt- or Meta-modifiers are used to add a parameter to the escape sequence returned by a numbered function-key.

The resource values are similar to modifyCursorKeys : Set it to -1 to permit the user to use shift- and control-modifiers to construct function-key strings using the normal encoding scheme. If modifyFunctionKeys is zero, xterm uses Control- and Shift-modifiers to allow the user to construct numbered function-keys beyond the set provided by the keyboard: Control.

Like modifyCursorKeys, tells xterm to construct an escape sequence for other keys such as " 2 " when modified by Control-, Alt- or Meta- modifiers. This feature does not apply to function keys and well-defined keys such as Esc or the control keys. The default is " 0 ": 0. Specifies the maximum time in milliseconds between multi-click select events.

The default is " " milliseconds. Specifies whether or not scrolling should be done asynchronously. Specifies the number of characters from the right margin at which the margin bell should be rung, when enabled by the marginBell resource. If " true ", xterm checks if NumLock is used as a modifier.

If so, this modifier is used to simplify the logic when implementing special NumLock for the sunKeyboard resource. Also when sunKeyboard is " false " , similar logic is used to find the modifier associated with the left and right Alt keys. If " true ", xterm will use old-style control sequences for function keys F1 to F4, for compatibility with X Consortium xterm.

Specify selection behavior in response to multiple mouse clicks. A single mouse click is always interpreted as described in the Selection section see Pointer Usage. Multiple mouse clicks using the button which activates the select-start action are interpreted according to the resource values of on2Clicks , etc. The resource value can be one of these: word. Select a "word" as determined by the charClass resource.

Select a group of adjacent lines counting wrapping. The selection stops on a blank line, and does not extend outside the current page. No selection action is associated with this resource.

The xterm command interprets it as the end of the list. For example, you may use it to disable triple and higher clicking by setting on3Clicks to " none ". Specifies when the pointer may be hidden as the user types. It will be redisplayed if the user moves the mouse, or clicks one of its buttons: 0. Specifies whether the window would be raised when Control-G is received. If the window is iconified, this has no effect. However, the zIconBeep resource provides you with the ability to see which iconified windows have sounded a bell.

Tells xterm which types of preedit preconversion string to display. The default is " OverTheSpot,Root ". Specifies whether to print graphic attributes along with the text. A real DEC VTxxx terminal will print the underline, highlighting codes but your printer may not handle these. When the print-immediate action is invoked, xterm prints the screen contents directly to a file.

Set this resource to the prefix of the file name a timestamp will be appended to the actual name. If xterm exits with an X error, e. To enable the feature, set this resource to the prefix of the file name a timestamp will be appended to the actual name. However, when the print-on-error action is invoked, if the string is empty, then " XTermError " is used.

You can use the printModeImmediate resource to tell it to use escape sequences to reconstruct the video attributes and colors. This uses the same values as the printAttributes resource. The default is " 0 ". You can use the printModeOnXError resource to tell it to use escape sequences to reconstruct the video attributes and colors. Specify the range of text that is printed to a file when the print-immediately action is invoked.

In that case, only the alternate screen is selectd. The default is " 9 ", which selects the current visible screen plus saved lines, with no special case for the alternated screen. Specify the range of text that is printed to a file when the print-on-error action is invoked. The resource value is interpreted the same as in printOptsImmediate. If " true ", xterm will close the printer a pipe when the application switches the printer offline with a Media Copy command.

Specifies a shell command to which xterm will open a pipe when the first MC Media Copy command is initiated. If the resource value is given as an empty string, the printer is disabled. Specifies the printer control mode. A " 1 " selects autoprint mode, which causes xterm to print a line from the screen when you move the cursor off that line with a line feed, form feed or vertical tab character, or an autowrap occurs.

Autoprint mode is overridden by printer controller mode a " 2 " , which causes all of the output to be directed to the printer. Controls whether a print page function will print the entire page true , or only the portion within the scrolling margins false. Controls whether a form feed is sent to the printer at the end of a print page function. Controls whether a newline is sent to the printer at the end of a print page function. Controls whether the cursor is repainted when NotifyGrab and NotifyUngrab event types are received during change of focus.

If xterm is built with the Xft library, this controls whether the faceName resource is used. The default is " default ". The resource values are strings , evaluated as booleans after startup.

If there is no value for faceName , disable the feature and use the normal bitmap font. If there is no faceName resource set, then runtime switching to TrueType fonts is disabled. That is normally " mono ". Affects the behavior when the window is resized to be taller or shorter.

NorthWest specifies that the top line of text on the screen stay fixed. If the window is made shorter, lines are dropped from the bottom; if the window is made taller, blank lines are added at the bottom. This is compatible with the behavior in R4. SouthWest the default specifies that the bottom line of text on the screen stay fixed. If the window is made taller, additional saved lines will be scrolled down onto the screen; if the window is made shorter, lines will be scrolled off the top of the screen, and the top saved lines will be dropped.

Tells xterm how many times to retry, in case the input-method server is not responding. This is a different issue than unsupported preedit type, etc. You may encounter retries if your X configuration and its libraries are missing pieces. Setting this resource to zero " 0 " will cancel the retrying. The default is " 3 ". Specifies whether or not reverse video should be simulated.

In particular, the X Toolkit sets the reverseVideo resource when the -rv option is used. Instead, it examines the resource values to reconstruct the command-line options, and determine which of the colors is the user's intended foreground, etc. Their actual values are irrelevant to the reverse video function; some users prefer the X defaults black text on a white background , others prefer white text on a black background.

This exchanges the current foreground and background colors of the VT widget, and repaints the screen. Because of the X resource hierarchy, the reverseVideo resource applies to more than the VT widget. Programs running in an xterm can also use control sequences to enable the VT reverse video mode.

These are independent of the reverseVideo resource and the menu entry. Specifies whether or not reverse-wraparound should be enabled. This corresponds to xterm 's private mode Specifies whether or not the scrollbar should be displayed on the right rather than the left. Specifies the number of lines to save beyond the top of the screen when a scrollbar is turned on.

Specifies the width of the scrollbar border. Note that this is drawn to overlap the border of the xterm window. Modifying the scrollbar's border affects only the line between the VT widget and the scrollbar. The default value is 1. Specifies whether or not pressing a key should automatically cause the scrollbar to go to the bottom of the scrolling region.

Specifies the number of lines that the scroll-back and scroll-forw actions should use as a default. Specifies whether or not output to the terminal should automatically cause the scrollbar to go to the bottom of the scrolling region. The set-select action can change this at runtime, allowing the user to work with programs that handle only one of these mechanisms.

Tells xterm whether to display text with blink-attribute the same as bold. If xterm has not been configured to support blinking text, the default is " true ", which corresponds to older versions of xterm , otherwise the default is " false ". Tells xterm whether to display a box outlining places where a character has been used that the font does not represent.

For debugging xterm and applications that may manipulate the wrapped-line flag by writing text at the right margin, show a mark on the right inner-border of the window. The mark shows which lines have the flag set. Specifies whether or not the entries in the "Main Options" menu for sending signals to xterm should be disallowed. Specifies the preferred size and position of the Tektronix window.

Specifies whether or not the escape sequence to enter Tektronix mode should be ignored. Specifies whether or not the Tektronix mode window should start in its smallest size if no explicit geometry is given. This is useful when running xterm on displays with small screens. Specifies whether or not xterm should start up in Tektronix mode. Specifies whether xterm should scroll to a new page when processing the ti termcap entry, i.

This is only in effect if titeInhibit is " true ", because the intent of this option is to provide a picture of the full-screen application's display on the scrollback without wiping out the text that would be shown before the application was initialized.

The default for this resource is " false ". Specifies whether or not xterm should remove ti and te termcap entries used to switch between alternate screens on startup of many screen-oriented programs from the TERMCAP string. If set, xterm also ignores the escape sequence to switch to the alternate screen. Either can be encoded in hexadecimal. The default for this resource is " 0 ".

Specifies the key and button bindings for menus, selections, "programmed strings", etc. The translations resource, which provides much of xterm 's configurability, is a feature of the X Toolkit Intrinsics library Xt. See the Actions section. If you set highlightSelection , you can see the text that is selected, including any trailing spaces. Clearing the screen or a line resets it to a state containing no spaces. Some lines may contain trailing spaces when an application writes them to the screen.

However, you may not wish to paste lines with trailing spaces. If this resource is true, xterm will trim trailing spaces from text that is selected. It does not affect spaces which result in a wrapped line, nor will it trim the trailing newline from your selection. This specifies whether or not text with the underline attribute should be underlined.

It may be desirable to disable underlining when color is being used for the underline attribute. Tell xterm whether to use clipping to keep from producing dots outside the text drawing area. Originally used to work around for overstriking effects, this is also needed to work with some incorrectly-sized fonts. This specifies whether xterm will run in UTF-8 mode. If you set this resource, xterm also sets the wideChars resource as a side-effect.

The resource can be set via the menu entry "UTF-8 Encoding". The default is "default". UTF-8 mode is initially off. The command-line option -u8 sets the resource to this value.

This is the default value of the resource. It is changed during initialization depending on whether the locale resource was set, to false 0 or always 2. See the locale resource for additional discussion of non-UTF-8 locales. If you want to set the value of utf8 , it should be in this range. Other nonzero values are treated the same as " 1 ", i. See the discussion of the locale resource. The resource can be set via the menu entry "UTF-8 Fonts". Use the ISO fonts.

The menu entry is enabled, allowing the choice of fonts to be changed at runtime. Use the UTF-8 fonts. Print [4]Shotts, Jr. William E. California: No Starch Press, Print Articles on DifferenceBetween. User assumes all risk of use, damage, or injury.

You agree that we have no liability for any damages. What is Terminal? What is Xterm? Difference between xterm and Terminal Basic Both Terminal and xterm are terminal emulator programs that allow the use of terminal in graphical environment. Process Management Users can have several instances of xterm running at once on the same display meaning each window corresponds to a separate process with each one providing independent input and output for a shell or process running it.

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