A string variable that controls the text color and background when displaying the text in the active region (see the description of enable-active-region below). This string must not take up any physical character positions on the display, so it should consist only of terminal escape sequences. It is output to the terminal before displaying the text in the active region. This variable is reset to the default value whenever the terminal type changes. The default value is the string that puts the terminal in standout mode, as obtained from the terminal’s terminfo description. A sample value might be ‘\e[01;33m’.

A string variable that “undoes” the effects of active-region-start-color and restores “normal” terminal display appearance after displaying text in the active region. This string must not take up any physical character positions on the display, so it should consist only of terminal escape sequences. It is output to the terminal after displaying the text in the active region. This variable is reset to the default value whenever the terminal type changes. The default value is the string that restores the terminal from standout mode, as obtained from the terminal’s terminfo description. A sample value might be ‘\e[0m’.

Controls what happens when Readline wants to ring the terminal bell. If set to ‘none’, Readline never rings the bell. If set to ‘visible’, Readline uses a visible bell if one is available. If set to ‘audible’ (the default), Readline attempts to ring the terminal’s bell.

If set to ‘on’ (the default), Readline attempts to bind the control characters that are treated specially by the kernel’s terminal driver to their Readline equivalents. These override the default Readline bindings described here. Type ‘stty -a’ at a Bash prompt to see your current terminal settings, including the special control characters (usually cchars).

If set to ‘on’, Readline attempts to briefly move the cursor to an opening parenthesis when a closing parenthesis is inserted. The default is ‘off’.

If set to ‘on’, when listing completions, Readline displays the common prefix of the set of possible completions using a different color. The color definitions are taken from the value of the LS_COLORS environment variable. If there is a color definition in LS_COLORS for the custom suffix ‘readline-colored-completion-prefix’, Readline uses this color for the common prefix instead of its default. The default is ‘off’.

If set to ‘on’, Readline displays possible completions using different colors to indicate their file type. The color definitions are taken from the value of the LS_COLORS environment variable. The default is ‘off’.

The string to insert at the beginning of the line by the insert-comment command. The default value is "#".

The number of screen columns used to display possible matches when performing completion. The value is ignored if it is less than 0 or greater than the terminal screen width. A value of 0 causes matches to be displayed one per line. The default value is -1.

If set to ‘on’, Readline performs filename matching and completion in a case-insensitive fashion. The default value is ‘off’.

If set to ‘on’, and completion-ignore-case is enabled, Readline treats hyphens (‘-’) and underscores (‘_’) as equivalent when performing case-insensitive filename matching and completion. The default value is ‘off’.

The maximum length in characters of the common prefix of a list of possible completions that is displayed without modification. When set to a value greater than zero, Readline replaces common prefixes longer than this value with an ellipsis when displaying possible completions. If a completion begins with a period, and Readline is completing filenames, it uses three underscores instead of an ellipsis.

The number of possible completions that determines when the user is asked whether the list of possibilities should be displayed. If the number of possible completions is greater than or equal to this value, Readline asks whether or not the user wishes to view them; otherwise, Readline simply lists the completions. This variable must be set to an integer value greater than or equal to zero. A zero value means Readline should never ask; negative values are treated as zero. The default limit is 100.

If set to ‘on’, Readline converts characters it reads that have the eighth bit set to an ASCII key sequence by clearing the eighth bit and prefixing an ESC character, converting them to a meta-prefixed key sequence. The default value is ‘on’, but Readline sets it to ‘off’ if the locale contains characters whose encodings may include bytes with the eighth bit set. This variable is dependent on the LC_CTYPE locale category, and may change if the locale changes. This variable also affects key bindings; see the description of force-meta-prefix below.

If set to ‘On’, Readline inhibits word completion. Completion characters are inserted into the line as if they had been mapped to self-insert. The default is ‘off’.

When set to ‘on’, on operating systems that indicate they support it, Readline echoes a character corresponding to a signal generated from the keyboard. The default is ‘on’.

The editing-mode variable controls the default set of key bindings. By default, Readline starts up in emacs editing mode, where the keystrokes are most similar to Emacs. This variable can be set to either ‘emacs’ or ‘vi’.

If the show-mode-in-prompt variable is enabled, this string is displayed immediately before the last line of the primary prompt when emacs editing mode is active. The value is expanded like a key binding, so the standard set of meta- and control- prefixes and backslash escape sequences is available. The ‘\1’ and ‘\2’ escapes begin and end sequences of non-printing characters, which can be used to embed a terminal control sequence into the mode string. The default is ‘@’.

point is the current cursor position, and mark refers to a saved cursor position (see Commands For Moving). The text between the point and mark is referred to as the region. When this variable is set to ‘On’, Readline allows certain commands to designate the region as active. When the region is active, Readline highlights the text in the region using the value of the active-region-start-color, which defaults to the string that enables the terminal’s standout mode. The active region shows the text inserted by bracketed-paste and any matching text found by incremental and non-incremental history searches. The default is ‘On’.

When set to ‘On’, Readline configures the terminal to insert each paste into the editing buffer as a single string of characters, instead of treating each character as if it had been read from the keyboard. This is called putting the terminal into bracketed paste mode; it prevents Readline from executing any editing commands bound to key sequences appearing in the pasted text. The default is ‘On’.

When set to ‘on’, Readline tries to enable the application keypad when it is called. Some systems need this to enable the arrow keys. The default is ‘off’.

When set to ‘on’, Readline tries to enable any meta modifier key the terminal claims to support when it is called. On many terminals, the Meta key is used to send eight-bit characters; this variable checks for the terminal capability that indicates the terminal can enable and disable a mode that sets the eighth bit of a character (0200) if the Meta key is held down when the character is typed (a meta character). The default is ‘on’.

If set to ‘on’, Readline attempts tilde expansion when it attempts word completion. The default is ‘off’.

If set to ‘on’, Readline modifies its behavior when binding key sequences containing \M- or Meta- (see Key Bindings in Readline Init File Syntax) by converting a key sequence of the form \M-C or Meta-C to the two-character sequence ESC C (adding the meta prefix). If force-meta-prefix is set to ‘off’ (the default), Readline uses the value of the convert-meta variable to determine whether to perform this conversion: if convert-meta is ‘on’, Readline performs the conversion described above; if it is ‘off’, Readline converts C to a meta character by setting the eighth bit (0200). The default is ‘off’.

If set to ‘on’, the history code attempts to place the point (the current cursor position) at the same location on each history line retrieved with previous-history or next-history. The default is ‘off’.

Set the maximum number of history entries saved in the history list. If set to zero, any existing history entries are deleted and no new entries are saved. If set to a value less than zero, the number of history entries is not limited. By default, Bash sets the maximum number of history entries to the value of the HISTSIZE shell variable. If you try to set history-size to a non-numeric value, the maximum number of history entries will be set to 500.

Setting this variable to ‘on’ means that the text of the lines being edited will scroll horizontally on a single screen line when the lines are longer than the width of the screen, instead of wrapping onto a new screen line. This variable is automatically set to ‘on’ for terminals of height 1. By default, this variable is set to ‘off’.

If set to ‘on’, Readline enables eight-bit input (that is, it does not clear the eighth bit in the characters it reads), regardless of what the terminal claims it can support. The default value is ‘off’, but Readline sets it to ‘on’ if the locale contains characters whose encodings may include bytes with the eighth bit set. This variable is dependent on the LC_CTYPE locale category, and its value may change if the locale changes. The name meta-flag is a synonym for input-meta.

The string of characters that should terminate an incremental search without subsequently executing the character as a command (see Searching for Commands in the History). If this variable has not been given a value, the characters ESC and C-j terminate an incremental search.

Sets Readline’s idea of the current keymap for key binding commands. Built-in keymap names are emacs, emacs-standard, emacs-meta, emacs-ctlx, vi, vi-move, vi-command, and vi-insert. vi is equivalent to vi-command (vi-move is also a synonym); emacs is equivalent to emacs-standard. Applications may add additional names. The default value is emacs; the value of the editing-mode variable also affects the default keymap.

Specifies the duration Readline will wait for a character when reading an ambiguous key sequence (one that can form a complete key sequence using the input read so far, or can take additional input to complete a longer key sequence). If Readline doesn’t receive any input within the timeout, it uses the shorter but complete key sequence. Readline uses this value to determine whether or not input is available on the current input source (rl_instream by default). The value is specified in milliseconds, so a value of 1000 means that Readline will wait one second for additional input. If this variable is set to a value less than or equal to zero, or to a non-numeric value, Readline waits until another key is pressed to decide which key sequence to complete. The default value is 500.

If set to ‘on’, completed directory names have a slash appended. The default is ‘on’.

When this variable is set to ‘on’, Readline displays an asterisk (‘*’) at the start of history lines which have been modified. This variable is ‘off’ by default.

If set to ‘on’, completed names which are symbolic links to directories have a slash appended, subject to the value of mark-directories. The default is ‘off’.

This variable, when set to ‘on’, forces Readline to match files whose names begin with a ‘.’ (hidden files) when performing filename completion. If set to ‘off’, the user must include the leading ‘.’ in the filename to be completed. This variable is ‘on’ by default.

If set to ‘on’, menu completion displays the common prefix of the list of possible completions (which may be empty) before cycling through the list. The default is ‘off’.

If set to ‘on’, Readline displays characters with the eighth bit set directly rather than as a meta-prefixed escape sequence. The default is ‘off’, but Readline sets it to ‘on’ if the locale contains characters whose encodings may include bytes with the eighth bit set. This variable is dependent on the LC_CTYPE locale category, and its value may change if the locale changes.

If set to ‘on’, Readline uses an internal pager resembling more(1) to display a screenful of possible completions at a time. This variable is ‘on’ by default.

See bell-style.

If set to ‘on’, Readline displays completions with matches sorted horizontally in alphabetical order, rather than down the screen. The default is ‘off’.

If set to ‘on’, Readline will undo all changes to history lines before returning when executing accept-line. By default, history lines may be modified and retain individual undo lists across calls to readline(). The default is ‘off’.

If set to ‘on’, Readline performs incremental and non-incremental history list searches in a case-insensitive fashion. The default value is ‘off’.

This alters the default behavior of the completion functions. If set to ‘on’, words which have more than one possible completion cause the matches to be listed immediately instead of ringing the bell. The default value is ‘off’.

This alters the default behavior of the completion functions in a fashion similar to show-all-if-ambiguous. If set to ‘on’, words which have more than one possible completion without any possible partial completion (the possible completions don’t share a common prefix) cause the matches to be listed immediately instead of ringing the bell. The default value is ‘off’.

If set to ‘on’, add a string to the beginning of the prompt indicating the editing mode: emacs, vi command, or vi insertion. The mode strings are user-settable (e.g., emacs-mode-string). The default value is ‘off’.

If set to ‘on’, this alters the default completion behavior when inserting a single match into the line. It’s only active when performing completion in the middle of a word. If enabled, Readline does not insert characters from the completion that match characters after point in the word being completed, so portions of the word following the cursor are not duplicated. For instance, if this is enabled, attempting completion when the cursor is after the first ‘e’ in ‘Makefile’ will result in ‘Makefile’ rather than ‘Makefilefile’, assuming there is a single possible completion. The default value is ‘off’.

If the show-mode-in-prompt variable is enabled, this string is displayed immediately before the last line of the primary prompt when vi editing mode is active and in command mode. The value is expanded like a key binding, so the standard set of meta- and control- prefixes and backslash escape sequences is available. The ‘\1’ and ‘\2’ escapes begin and end sequences of non-printing characters, which can be used to embed a terminal control sequence into the mode string. The default is ‘(cmd)’.

If the show-mode-in-prompt variable is enabled, this string is displayed immediately before the last line of the primary prompt when vi editing mode is active and in insertion mode. The value is expanded like a key binding, so the standard set of meta- and control- prefixes and backslash escape sequences is available. The ‘\1’ and ‘\2’ escapes begin and end sequences of non-printing characters, which can be used to embed a terminal control sequence into the mode string. The default is ‘(ins)’.

If set to ‘on’, a character denoting a file’s type is appended to the filename when listing possible completions. The default is ‘off’.