Provided by: readline-common_8.1.2-1_all bug

NAME

       readline - get a line from a user with editing

SYNOPSIS

       #include <stdio.h>
       #include <readline/readline.h>
       #include <readline/history.h>

       char *
       readline (const char *prompt);

COPYRIGHT

       Readline is Copyright (C) 1989-2020 Free Software Foundation,  Inc.

DESCRIPTION

       readline  will  read a line from the terminal and return it, using prompt as a prompt.  If prompt is NULL
       or the empty string, no prompt is issued.  The line returned is allocated with malloc(3); the caller must
       free it when finished.  The line returned has the final newline removed, so only the  text  of  the  line
       remains.

       readline  offers  editing capabilities while the user is entering the line.  By default, the line editing
       commands are similar to those of emacs.  A vi-style line editing interface is also available.

       This manual page describes only the most basic use of readline.  Much more  functionality  is  available;
       see The GNU Readline Library and The GNU History Library for additional information.

RETURN VALUE

       readline  returns  the  text  of  the  line  read.   A  blank  line  returns the empty string.  If EOF is
       encountered while reading a line, and the line is empty, NULL is returned.  If an  EOF  is  read  with  a
       non-empty line, it is treated as a newline.

NOTATION

       An Emacs-style notation is used to denote keystrokes.  Control keys are denoted by C-key, e.g., C-n means
       Control-N.  Similarly, meta keys are denoted by M-key, so M-x means Meta-X.  (On keyboards without a meta
       key,  M-x  means  ESC x, i.e., press the Escape key then the x key.  This makes ESC the meta prefix.  The
       combination M-C-x means ESC-Control-x, or press the Escape key then hold the Control key  while  pressing
       the x key.)

       Readline  commands  may  be  given  numeric  arguments, which normally act as a repeat count.  Sometimes,
       however, it is the sign of the argument that is significant.  Passing a negative argument  to  a  command
       that  acts in the forward direction (e.g., kill-line) causes that command to act in a backward direction.
       Commands whose behavior with arguments deviates from this are noted below.

       When a command is described as killing text, the text deleted is  saved  for  possible  future  retrieval
       (yanking).   The killed text is saved in a kill ring.  Consecutive kills cause the text to be accumulated
       into one unit, which can be yanked all at once.  Commands which do not kill text separate the  chunks  of
       text on the kill ring.

INITIALIZATION FILE

       Readline  is  customized  by  putting commands in an initialization file (the inputrc file).  The name of
       this file is taken from the value of the INPUTRC environment variable.  If that variable  is  unset,  the
       default  is  ~/.inputrc.   If  that  file   does  not  exist  or  cannot be read, the ultimate default is
       /etc/inputrc.  When a program which uses the readline library starts up, the init file is read,  and  the
       key  bindings  and variables are set.  There are only a few basic constructs allowed in the readline init
       file.  Blank lines are ignored.  Lines beginning with a  #  are  comments.   Lines  beginning  with  a  $
       indicate  conditional  constructs.   Other lines denote key bindings and variable settings.  Each program
       using this library may add its own commands and bindings.

       For example, placing

              M-Control-u: universal-argument
       or
              C-Meta-u: universal-argument

       into the inputrc would make M-C-u execute the readline command universal-argument.

       The following symbolic character names are recognized while processing key bindings:  DEL,  ESC,  ESCAPE,
       LFD, NEWLINE, RET, RETURN, RUBOUT, SPACE, SPC, and TAB.

       In  addition to command names, readline allows keys to be bound to a string that is inserted when the key
       is pressed (a macro).

   Key Bindings
       The syntax for controlling key bindings in the inputrc file is simple.  All that is required is the  name
       of  the  command  or the text of a macro and a key sequence to which it should be bound.  The name may be
       specified in one of two ways: as a symbolic key name, possibly with Meta- or Control- prefixes, or  as  a
       key  sequence.   The  name and key sequence are separated by a colon.  There can be no whitespace between
       the name and the colon.

       When using the form keyname:function-name or macro, keyname is the name of a key spelled out in  English.
       For example:

              Control-u: universal-argument
              Meta-Rubout: backward-kill-word
              Control-o: "> output"

       In  the  above  example,  C-u is bound to the function universal-argument, M-DEL is bound to the function
       backward-kill-word, and C-o is bound to run the macro expressed on the  right  hand  side  (that  is,  to
       insert the text ``> output'' into the line).

       In  the  second  form, "keyseq":function-name or macro, keyseq differs from keyname above in that strings
       denoting an entire key sequence may be specified by placing the sequence within double quotes.  Some  GNU
       Emacs  style  key  escapes can be used, as in the following example, but the symbolic character names are
       not recognized.

              "\C-u": universal-argument
              "\C-x\C-r": re-read-init-file
              "\e[11~": "Function Key 1"

       In this example, C-u is again bound to the function universal-argument.  C-x C-r is bound to the function
       re-read-init-file, and ESC [ 1 1 ~ is bound to insert the text ``Function Key 1''.

       The full set of GNU Emacs style escape sequences available when specifying key sequences is
              \C-    control prefix
              \M-    meta prefix
              \e     an escape character
              \\     backslash
              \"     literal ", a double quote
              \'     literal ', a single quote

       In addition to the GNU Emacs style escape sequences, a second set of backslash escapes is available:
              \a     alert (bell)
              \b     backspace
              \d     delete
              \f     form feed
              \n     newline
              \r     carriage return
              \t     horizontal tab
              \v     vertical tab
              \nnn   the eight-bit character whose value is the octal value nnn (one to three digits)
              \xHH   the eight-bit character whose value is the hexadecimal value HH (one or two hex digits)

       When entering the text of a macro, single or double quotes should be used to indicate a macro definition.
       Unquoted text is assumed to be a function name.  In the macro body, the backslash escapes described above
       are expanded.  Backslash will quote any other character in the macro text, including " and '.

       Bash allows the current readline key bindings to be displayed or modified with the bind builtin  command.
       The  editing  mode  may  be  switched  during  interactive  use by using the -o option to the set builtin
       command.  Other programs using this library provide similar mechanisms.  The inputrc file may  be  edited
       and re-read if a program does not provide any other means to incorporate new bindings.

   Variables
       Readline  has variables that can be used to further customize its behavior.  A variable may be set in the
       inputrc file with a statement of the form

              set variable-name value

       Except where noted, readline variables  can  take  the  values  On  or  Off  (without  regard  to  case).
       Unrecognized  variable  names  are  ignored.   When  a variable value is read, empty or null values, "on"
       (case-insensitive), and "1" are equivalent to On.  All other values are equivalent to Off.  The variables
       and their default values are:

       bell-style (audible)
              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, readline attempts to ring the terminal's bell.
       bind-tty-special-chars (On)
              If set to On (the default), readline attempts to bind the control characters    treated  specially
              by the kernel's terminal driver to their readline equivalents.
       blink-matching-paren (Off)
              If  set  to  On,  readline  attempts  to  briefly move the cursor to an opening parenthesis when a
              closing parenthesis is inserted.
       colored-completion-prefix (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.
       colored-stats (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.
       comment-begin (``#'')
              The  string that is inserted in vi mode when the insert-comment command is executed.  This command
              is bound to M-# in emacs mode and to # in vi command mode.
       completion-display-width (-1)
              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
              will cause matches to be displayed one per line.  The default value is -1.
       completion-ignore-case (Off)
              If set to On, readline performs filename matching and completion in a case-insensitive fashion.
       completion-map-case (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.
       completion-prefix-display-length (0)
              The  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, common  prefixes  longer  than  this
              value are replaced with an ellipsis when displaying possible completions.
       completion-query-items (100)
              This  determines  when  the  user  is  queried  about  viewing  the number of possible completions
              generated by the possible-completions command.  It may be set to any integer value greater than or
              equal to zero.  If the number of possible completions is greater than or equal  to  the  value  of
              this  variable,  readline will ask whether or not the user wishes to view them; otherwise they are
              simply listed on the terminal.  A negative value causes readline to never ask.
       convert-meta (On)
              If set to On, readline will convert characters with the eighth bit set to an ASCII key sequence by
              stripping the eighth bit and prefixing it with an escape character (in effect, using escape as the
              meta prefix).  The default is On, but readline will set it to Off if the locale contains eight-bit
              characters.
       disable-completion (Off)
              If set to On, readline will inhibit word completion.  Completion characters will be inserted  into
              the line as if they had been mapped to self-insert.
       echo-control-characters (On)
              When  set  to  On, on operating systems that indicate they support it, readline echoes a character
              corresponding to a signal generated from the keyboard.
       editing-mode (emacs)
              Controls whether readline begins with a set of key bindings similar to Emacs or vi.   editing-mode
              can be set to either emacs or vi.
       emacs-mode-string (@)
              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.  Use the \1 and \2 escapes to begin and end sequences of non-printing characters, which
              can be used to embed a terminal control sequence into the mode string.
       enable-bracketed-paste (On)
              When set to On, readline will configure the terminal in a way that will enable it 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  can prevent pasted characters from being
              interpreted as editing commands.
       enable-keypad (Off)
              When set to On, readline will try to enable the  application  keypad  when  it  is  called.   Some
              systems need this to enable the arrow keys.
       enable-meta-key (On)
              When  set  to On, readline will try 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.
       expand-tilde (Off)
              If set to On, tilde expansion is performed when readline attempts word completion.
       history-preserve-point (Off)
              If set to On, the history code attempts to place point at the same location on each  history  line
              retrieved with previous-history or next-history.
       history-size (unset)
              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,  the  number  of  history  entries  is  not
              limited.   If an attempt is made to set history-size to a non-numeric value, the maximum number of
              history entries will be set to 500.
       horizontal-scroll-mode (Off)
              When set to On, makes readline use a single line for display, scrolling the input horizontally  on
              a  single  screen  line when it becomes longer than the screen width rather than wrapping to a new
              line.  This setting is automatically enabled for terminals of height 1.
       input-meta (Off)
              If set to On, readline will enable eight-bit input (that is, it will not clear the eighth  bit  in
              the  characters  it  reads),  regardless  of  what  the  terminal claims it can support.  The name
              meta-flag is a synonym for this variable.  The default is Off, but readline will set it to  On  if
              the locale contains eight-bit characters.
       isearch-terminators (``C-[ C-J'')
              The  string  of  characters  that  should  terminate  an  incremental  search without subsequently
              executing the character as a command.  If this variable has not been given a value, the characters
              ESC and C-J will terminate an incremental search.
       keymap (emacs)
              Set the current readline keymap.  The set of legal keymap names is emacs,  emacs-standard,  emacs-
              meta,  emacs-ctlx,  vi, vi-move, vi-command, and vi-insert.  vi is equivalent to vi-command; emacs
              is equivalent to emacs-standard.  The default value is emacs.   The  value  of  editing-mode  also
              affects the default keymap.
       keyseq-timeout (500)
              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 no input is received within the timeout, readline
              will use the shorter but complete key sequence.  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  will  wait  until
              another key is pressed to decide which key sequence to complete.
       mark-directories (On)
              If set to On, completed directory names have a slash appended.
       mark-modified-lines (Off)
              If set to On, history lines that have been modified are displayed with a preceding asterisk (*).
       mark-symlinked-directories (Off)
              If  set  to  On,  completed  names  which  are symbolic links to directories have a slash appended
              (subject to the value of mark-directories).
       match-hidden-files (On)
              This variable, when set to On, causes readline to match files whose names begin with a `.' (hidden
              files) when performing filename completion.  If set to Off, the leading `.' must  be  supplied  by
              the user in the filename to be completed.
       menu-complete-display-prefix (Off)
              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.
       output-meta (Off)
              If set to On, readline will display characters with the eighth bit set directly rather than  as  a
              meta-prefixed  escape  sequence.  The default is Off, but readline will set it to On if the locale
              contains eight-bit characters.
       page-completions (On)
              If set to On, readline uses an internal  more-like  pager  to  display  a  screenful  of  possible
              completions at a time.
       print-completions-horizontally (Off)
              If  set  to On, readline will display completions with matches sorted horizontally in alphabetical
              order, rather than down the screen.
       revert-all-at-newline (Off)
              If set to On, readline will undo all changes to history lines before returning when accept-line is
              executed.  By default, history lines may be modified and retain individual undo lists across calls
              to readline.
       show-all-if-ambiguous (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.
       show-all-if-unmodified (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.
       show-mode-in-prompt (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).
       skip-completed-text (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.
       vi-cmd-mode-string ((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 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.  Use the \1 and \2 escapes to  begin  and  end  sequences  of  non-
              printing characters, which can be used to embed a terminal control sequence into the mode string.
       vi-ins-mode-string ((ins))
              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.  Use the \1 and \2 escapes to  begin  and  end  sequences  of  non-
              printing characters, which can be used to embed a terminal control sequence into the mode string.
       visible-stats (Off)
              If  set  to  On,  a  character  denoting  a  file's type as reported by stat(2) is appended to the
              filename when listing possible completions.

   Conditional Constructs
       Readline implements a facility similar in spirit  to  the  conditional  compilation  features  of  the  C
       preprocessor  which  allows  key  bindings  and variable settings to be performed as the result of tests.
       There are four parser directives used.

       $if    The $if construct allows bindings to be made based on the editing mode, the terminal  being  used,
              or  the  application using readline.  The text of the test, after any comparison operator, extends
              to the end of the line; unless otherwise noted, no characters are required to isolate it.

              mode   The mode= form of the $if directive is used to test whether readline  is  in  emacs  or  vi
                     mode.   This  may  be used in conjunction with the set keymap command, for instance, to set
                     bindings in the emacs-standard and emacs-ctlx keymaps only if readline is starting  out  in
                     emacs mode.

              term   The  term=  form may be used to include terminal-specific key bindings, perhaps to bind the
                     key sequences output by the terminal's function keys.  The word on the right side of the  =
                     is tested against the full name of the terminal and the portion of the terminal name before
                     the first -.  This allows sun to match both sun and sun-cmd, for instance.

              version
                     The  version  test  may  be used to perform comparisons against specific readline versions.
                     The version expands to the current readline  version.   The  set  of  comparison  operators
                     includes  =, (and ==), !=, <=, >=, <, and >.  The version number supplied on the right side
                     of the operator consists of a major version number,  an  optional  decimal  point,  and  an
                     optional minor version (e.g., 7.1). If the minor version is omitted, it is assumed to be 0.
                     The  operator may be separated from the string version and from the version number argument
                     by whitespace.

              application
                     The application construct is used to include application-specific settings.   Each  program
                     using  the  readline library sets the application name, and an initialization file can test
                     for a particular value.  This could be used to bind key sequences to functions useful for a
                     specific program.  For instance, the following command adds a key sequence that quotes  the
                     current or previous word in bash:

                     $if Bash
                     # Quote the current or previous word
                     "\C-xq": "\eb\"\ef\""
                     $endif

              variable
                     The  variable  construct  provides simple equality tests for readline variables and values.
                     The permitted comparison operators are =, ==, and !=.  The variable name must be  separated
                     from the comparison operator by whitespace; the operator may be separated from the value on
                     the  right  hand  side  by  whitespace.   Both  string and boolean variables may be tested.
                     Boolean variables must be tested against the values on and off.

       $endif This command, as seen in the previous example, terminates an $if command.

       $else  Commands in this branch of the $if directive are executed if the test fails.

       $include
              This directive takes a single filename as an argument and reads commands and  bindings  from  that
              file.  For example, the following directive would read /etc/inputrc:

              $include  /etc/inputrc

SEARCHING

       Readline  provides  commands  for  searching through the command history for lines containing a specified
       string.  There are two search modes: incremental and non-incremental.

       Incremental searches begin before the user has finished typing the search string.  As each  character  of
       the  search  string is typed, readline displays the next entry from the history matching the string typed
       so far.  An incremental search requires only as many characters as needed to  find  the  desired  history
       entry.  To search backward in the history for a particular string, type C-r.  Typing C-s searches forward
       through the history.  The characters present in the value of the isearch-terminators variable are used to
       terminate  an  incremental  search.   If  that  variable has not been assigned a value the Escape and C-J
       characters will terminate an incremental search.  C-G will abort an incremental search  and  restore  the
       original line.  When the search is terminated, the history entry containing the search string becomes the
       current line.

       To  find  other  matching  entries in the history list, type C-s or C-r as appropriate.  This will search
       backward or forward in the history for the next line matching the search string typed so far.  Any  other
       key  sequence  bound  to  a  readline  command  will  terminate the search and execute that command.  For
       instance, a newline will terminate the search and accept the line, thereby executing the command from the
       history list.  A movement command will terminate the search, make the last line found the  current  line,
       and begin editing.

       Non-incremental  searches  read  the  entire search string before starting to search for matching history
       lines.  The search string may be typed by the user or be part of the contents of the current line.

EDITING COMMANDS

       The following is a list of the names of the commands and the default key  sequences  to  which  they  are
       bound.  Command names without an accompanying key sequence are unbound by default.

       In  the  following descriptions, point refers to the current cursor position, and mark refers to a cursor
       position saved by the set-mark command.  The text between the point  and  mark  is  referred  to  as  the
       region.

   Commands for Moving
       beginning-of-line (C-a)
              Move to the start of the current line.
       end-of-line (C-e)
              Move to the end of the line.
       forward-char (C-f)
              Move forward a character.
       backward-char (C-b)
              Move back a character.
       forward-word (M-f)
              Move  forward to the end of the next word.  Words are composed of alphanumeric characters (letters
              and digits).
       backward-word (M-b)
              Move back to the start of the current or  previous  word.   Words  are  composed  of  alphanumeric
              characters (letters and digits).
       previous-screen-line
              Attempt  to  move  point  to the same physical screen column on the previous physical screen line.
              This will not have the desired effect if the current Readline line does not take up more than  one
              physical line or if point is not greater than the length of the prompt plus the screen width.
       next-screen-line
              Attempt  to  move  point to the same physical screen column on the next physical screen line. This
              will not have the desired effect if the current Readline line does  not  take  up  more  than  one
              physical  line or if the length of the current Readline line is not greater than the length of the
              prompt plus the screen width.
       clear-display (M-C-l)
              Clear the screen and, if possible, the terminal's scrollback buffer, then redraw the current line,
              leaving the current line at the top of the screen.
       clear-screen (C-l)
              Clear the screen, then redraw the current line, leaving the current line at the top of the screen.
              With an argument, refresh the current line without clearing the screen.
       redraw-current-line
              Refresh the current line.

   Commands for Manipulating the History
       accept-line (Newline, Return)
              Accept the line regardless of where the cursor is.  If this line is non-empty, it may be added  to
              the  history  list  for future recall with add_history().  If the line is a modified history line,
              the history line is restored to its original state.
       previous-history (C-p)
              Fetch the previous command from the history list, moving back in the list.
       next-history (C-n)
              Fetch the next command from the history list, moving forward in the list.
       beginning-of-history (M-<)
              Move to the first line in the history.
       end-of-history (M->)
              Move to the end of the input history, i.e., the line currently being entered.
       reverse-search-history (C-r)
              Search backward starting at the current line and moving `up' through  the  history  as  necessary.
              This is an incremental search.
       forward-search-history (C-s)
              Search  forward  starting  at the current line and moving `down' through the history as necessary.
              This is an incremental search.
       non-incremental-reverse-search-history (M-p)
              Search backward through the history starting at the current line using  a  non-incremental  search
              for a string supplied by the user.
       non-incremental-forward-search-history (M-n)
              Search  forward  through  the  history using a non-incremental search for a string supplied by the
              user.
       history-search-backward
              Search backward through the history for the string of characters between the start of the  current
              line  and  the current cursor position (the point).  The search string must match at the beginning
              of a history line.  This is a non-incremental search.
       history-search-forward
              Search forward through the history for the string of characters between the start of  the  current
              line  and  the point.  The search string must match at the beginning of a history line.  This is a
              non-incremental search.
       history-substring-search-backward
              Search backward through the history for the string of characters between the start of the  current
              line  and  the  current  cursor  position  (the point).  The search string may match anywhere in a
              history line.  This is a non-incremental search.
       history-substring-search-forward
              Search forward through the history for the string of characters between the start of  the  current
              line  and  the  point.   The  search  string may match anywhere in a history line.  This is a non-
              incremental search.
       yank-nth-arg (M-C-y)
              Insert the first argument to the previous command (usually the second word on the  previous  line)
              at  point.   With  an  argument n, insert the nth word from the previous command (the words in the
              previous command begin with word 0).  A negative argument inserts the nth word from the end of the
              previous command.  Once the argument n is computed, the argument  is  extracted  as  if  the  "!n"
              history expansion had been specified.
       yank-last-arg (M-., M-_)
              Insert  the  last  argument to the previous command (the last word of the previous history entry).
              With a numeric argument, behave exactly like yank-nth-arg.  Successive calls to yank-last-arg move
              back through the history list, inserting the last word (or the word specified by the  argument  to
              the  first  call)  of  each line in turn.  Any numeric argument supplied to these successive calls
              determines the direction to move through the history.  A negative argument switches the  direction
              through  the  history (back or forward).  The history expansion facilities are used to extract the
              last argument, as if the "!$" history expansion had been specified.
       operate-and-get-next (C-o)
              Accept the current line for return to the calling application as if a newline  had  been  entered,
              and  fetch  the  next  line  relative to the current line from the history for editing.  A numeric
              argument, if supplied, specifies the history entry to use instead of the current line.

   Commands for Changing Text
       end-of-file (usually C-d)
              The character indicating end-of-file as set, for example, by ``stty''.  If this character is  read
              when  there  are  no  characters  on the line, and point is at the beginning of the line, Readline
              interprets it as the end of input and returns EOF.
       delete-char (C-d)
              Delete the character at point.  If this function is bound to the same character  as  the  tty  EOF
              character, as C-d commonly is, see above for the effects.
       backward-delete-char (Rubout)
              Delete  the  character behind the cursor.  When given a numeric argument, save the deleted text on
              the kill ring.
       forward-backward-delete-char
              Delete the character under the cursor, unless the cursor is at the end of the line, in which  case
              the character behind the cursor is deleted.
       quoted-insert (C-q, C-v)
              Add  the next character that you type to the line verbatim.  This is how to insert characters like
              C-q, for example.
       tab-insert (M-TAB)
              Insert a tab character.
       self-insert (a, b, A, 1, !, ...)
              Insert the character typed.
       transpose-chars (C-t)
              Drag the character before point forward over the character at point, moving point forward as well.
              If point is at the end of the  line,  then  this  transposes  the  two  characters  before  point.
              Negative arguments have no effect.
       transpose-words (M-t)
              Drag  the  word  before  point past the word after point, moving point over that word as well.  If
              point is at the end of the line, this transposes the last two words on the line.
       upcase-word (M-u)
              Uppercase the current (or following) word.  With a negative argument, uppercase the previous word,
              but do not move point.
       downcase-word (M-l)
              Lowercase the current (or following) word.  With a negative argument, lowercase the previous word,
              but do not move point.
       capitalize-word (M-c)
              Capitalize the current (or following) word.  With a negative  argument,  capitalize  the  previous
              word, but do not move point.
       overwrite-mode
              Toggle  overwrite  mode.   With an explicit positive numeric argument, switches to overwrite mode.
              With an explicit non-positive numeric argument, switches to insert  mode.   This  command  affects
              only  emacs  mode;  vi  mode does overwrite differently.  Each call to readline() starts in insert
              mode.  In overwrite mode, characters bound to self-insert replace the text at  point  rather  than
              pushing  the  text  to  the right.  Characters bound to backward-delete-char replace the character
              before point with a space.  By default, this command is unbound.

   Killing and Yanking
       kill-line (C-k)
              Kill the text from point to the end of the line.
       backward-kill-line (C-x Rubout)
              Kill backward to the beginning of the line.
       unix-line-discard (C-u)
              Kill backward from point to the beginning of the line.  The killed text is saved on the kill-ring.
       kill-whole-line
              Kill all characters on the current line, no matter where point is.
       kill-word (M-d)
              Kill from point the end of the current word, or if between words, to the end  of  the  next  word.
              Word boundaries are the same as those used by forward-word.
       backward-kill-word (M-Rubout)
              Kill the word behind point.  Word boundaries are the same as those used by backward-word.
       unix-word-rubout (C-w)
              Kill the word behind point, using white space as a word boundary.  The killed text is saved on the
              kill-ring.
       unix-filename-rubout
              Kill the word behind point, using white space and the slash character as the word boundaries.  The
              killed text is saved on the kill-ring.
       delete-horizontal-space (M-\)
              Delete all spaces and tabs around point.
       kill-region
              Kill the text between the point and mark (saved cursor position).  This text is referred to as the
              region.
       copy-region-as-kill
              Copy the text in the region to the kill buffer.
       copy-backward-word
              Copy the word before point to the kill buffer.  The word boundaries are the same as backward-word.
       copy-forward-word
              Copy  the  word  following  point  to  the  kill  buffer.   The  word  boundaries  are the same as
              forward-word.
       yank (C-y)
              Yank the top of the kill ring into the buffer at point.
       yank-pop (M-y)
              Rotate the kill ring, and yank the new top.  Only works following yank or yank-pop.

   Numeric Arguments
       digit-argument (M-0, M-1, ..., M--)
              Add this digit to the argument already accumulating, or  start  a  new  argument.   M--  starts  a
              negative argument.
       universal-argument
              This  is  another  way to specify an argument.  If this command is followed by one or more digits,
              optionally with a leading minus sign, those  digits  define  the  argument.   If  the  command  is
              followed by digits, executing universal-argument again ends the numeric argument, but is otherwise
              ignored.   As  a  special  case,  if  this  command is immediately followed by a character that is
              neither a digit or minus sign, the argument count for the next command is multiplied by four.  The
              argument count is initially one, so executing this function the  first  time  makes  the  argument
              count four, a second time makes the argument count sixteen, and so on.

   Completing
       complete (TAB)
              Attempt  to  perform  completion  on  the  text  before point.  The actual completion performed is
              application-specific.  Bash, for instance, attempts completion treating the text as a variable (if
              the text begins with $), username (if the text begins with ~), hostname (if the text  begins  with
              @),  or  command  (including  aliases  and functions) in turn.  If none of these produces a match,
              filename completion is attempted.  Gdb, on the other hand, allows completion of program  functions
              and variables, and only attempts filename completion under certain circumstances.
       possible-completions (M-?)
              List  the  possible  completions  of the text before point.  When displaying completions, readline
              sets the number of columns used for display to the value of completion-display-width, the value of
              the environment variable COLUMNS, or the screen width, in that order.
       insert-completions (M-*)
              Insert  all  completions  of  the  text  before  point  that  would   have   been   generated   by
              possible-completions.
       menu-complete
              Similar  to  complete,  but replaces the word to be completed with a single match from the list of
              possible completions.  Repeated execution of menu-complete steps  through  the  list  of  possible
              completions,  inserting  each  match  in turn.  At the end of the list of completions, the bell is
              rung (subject to the setting of bell-style) and the original text is restored.  An argument  of  n
              moves n positions forward in the list of matches; a negative argument may be used to move backward
              through the list.  This command is intended to be bound to TAB, but is unbound by default.
       menu-complete-backward
              Identical  to  menu-complete,  but  moves backward through the list of possible completions, as if
              menu-complete had been given a negative argument.  This command is unbound by default.
       delete-char-or-list
              Deletes the character under the cursor if not at the beginning or end of the  line  (like  delete-
              char).  If at the end of the line, behaves identically to possible-completions.

   Keyboard Macros
       start-kbd-macro (C-x ()
              Begin saving the characters typed into the current keyboard macro.
       end-kbd-macro (C-x ))
              Stop saving the characters typed into the current keyboard macro and store the definition.
       call-last-kbd-macro (C-x e)
              Re-execute  the  last  keyboard  macro defined, by making the characters in the macro appear as if
              typed at the keyboard.
       print-last-kbd-macro ()
              Print the last keyboard macro defined in a format suitable for the inputrc file.

   Miscellaneous
       re-read-init-file (C-x C-r)
              Read in the contents of the inputrc file, and incorporate any  bindings  or  variable  assignments
              found there.
       abort (C-g)
              Abort  the  current  editing  command  and  ring  the  terminal's  bell (subject to the setting of
              bell-style).
       do-lowercase-version (M-A, M-B, M-x, ...)
              If the metafied character x is uppercase, run the command  that  is  bound  to  the  corresponding
              metafied lowercase character.  The behavior is undefined if x is already lowercase.
       prefix-meta (ESC)
              Metafy the next character typed.  ESC f is equivalent to Meta-f.
       undo (C-_, C-x C-u)
              Incremental undo, separately remembered for each line.
       revert-line (M-r)
              Undo  all  changes  made  to  this  line.  This is like executing the undo command enough times to
              return the line to its initial state.
       tilde-expand (M-&)
              Perform tilde expansion on the current word.
       set-mark (C-@, M-<space>)
              Set the mark to the point.  If a numeric argument is supplied, the mark is set to that position.
       exchange-point-and-mark (C-x C-x)
              Swap the point with the mark.  The current cursor position is set to the saved position,  and  the
              old cursor position is saved as the mark.
       character-search (C-])
              A character is read and point is moved to the next occurrence of that character.  A negative count
              searches for previous occurrences.
       character-search-backward (M-C-])
              A  character  is read and point is moved to the previous occurrence of that character.  A negative
              count searches for subsequent occurrences.
       skip-csi-sequence
              Read enough characters to consume a multi-key sequence such as those defined for  keys  like  Home
              and  End.   Such  sequences begin with a Control Sequence Indicator (CSI), usually ESC-[.  If this
              sequence is bound to "\[", keys producing such sequences will have  no  effect  unless  explicitly
              bound  to a readline command, instead of inserting stray characters into the editing buffer.  This
              is unbound by default, but usually bound to ESC-[.
       insert-comment (M-#)
              Without a numeric argument, the value of the readline comment-begin variable is  inserted  at  the
              beginning  of the current line.  If a numeric argument is supplied, this command acts as a toggle:
              if the characters at the beginning of the line do not match the value of comment-begin, the  value
              is inserted, otherwise the characters in comment-begin are deleted from the beginning of the line.
              In  either  case,  the  line  is  accepted  as  if a newline had been typed.  The default value of
              comment-begin makes the current line a shell comment.  If a numeric argument  causes  the  comment
              character to be removed, the line will be executed by the shell.
       dump-functions
              Print  all  of  the  functions and their key bindings to the readline output stream.  If a numeric
              argument is supplied, the output is formatted in such a way that it can be made part of an inputrc
              file.
       dump-variables
              Print all of the settable variables and their values to the readline output stream.  If a  numeric
              argument is supplied, the output is formatted in such a way that it can be made part of an inputrc
              file.
       dump-macros
              Print all of the readline key sequences bound to macros and the strings they output.  If a numeric
              argument is supplied, the output is formatted in such a way that it can be made part of an inputrc
              file.
       emacs-editing-mode (C-e)
              When in vi command mode, this causes a switch to emacs editing mode.
       vi-editing-mode (M-C-j)
              When in emacs editing mode, this causes a switch to vi editing mode.

DEFAULT KEY BINDINGS

       The  following  is  a  list of the default emacs and vi bindings.  Characters with the eighth bit set are
       written as M-<character>, and are referred to as metafied characters.  The printable ASCII characters not
       mentioned in the list of emacs standard bindings are  bound  to  the  self-insert  function,  which  just
       inserts  the  given character into the input line.  In vi insertion mode, all characters not specifically
       mentioned are bound to self-insert.  Characters assigned to signal generation by stty(1) or the  terminal
       driver,  such as C-Z or C-C, retain that function.  Upper and lower case metafied characters are bound to
       the same function in the emacs mode meta keymap.  The remaining  characters  are  unbound,  which  causes
       readline to ring the bell (subject to the setting of the bell-style variable).

   Emacs Mode
             Emacs Standard bindings

             "C-@"  set-mark
             "C-A"  beginning-of-line
             "C-B"  backward-char
             "C-D"  delete-char
             "C-E"  end-of-line
             "C-F"  forward-char
             "C-G"  abort
             "C-H"  backward-delete-char
             "C-I"  complete
             "C-J"  accept-line
             "C-K"  kill-line
             "C-L"  clear-screen
             "C-M"  accept-line
             "C-N"  next-history
             "C-P"  previous-history
             "C-Q"  quoted-insert
             "C-R"  reverse-search-history
             "C-S"  forward-search-history
             "C-T"  transpose-chars
             "C-U"  unix-line-discard
             "C-V"  quoted-insert
             "C-W"  unix-word-rubout
             "C-Y"  yank
             "C-]"  character-search
             "C-_"  undo
             " " to "/"  self-insert
             "0"  to "9"  self-insert
             ":"  to "~"  self-insert
             "C-?"  backward-delete-char

             Emacs Meta bindings

             "M-C-G"  abort
             "M-C-H"  backward-kill-word
             "M-C-I"  tab-insert
             "M-C-J"  vi-editing-mode
             "M-C-L"  clear-display
             "M-C-M"  vi-editing-mode
             "M-C-R"  revert-line
             "M-C-Y"  yank-nth-arg
             "M-C-["  complete
             "M-C-]"  character-search-backward
             "M-space"  set-mark
             "M-#"  insert-comment
             "M-&"  tilde-expand
             "M-*"  insert-completions
             "M--"  digit-argument
             "M-."  yank-last-arg
             "M-0"  digit-argument
             "M-1"  digit-argument
             "M-2"  digit-argument
             "M-3"  digit-argument
             "M-4"  digit-argument
             "M-5"  digit-argument
             "M-6"  digit-argument
             "M-7"  digit-argument
             "M-8"  digit-argument
             "M-9"  digit-argument
             "M-<"  beginning-of-history
             "M-="  possible-completions
             "M->"  end-of-history
             "M-?"  possible-completions
             "M-B"  backward-word
             "M-C"  capitalize-word
             "M-D"  kill-word
             "M-F"  forward-word
             "M-L"  downcase-word
             "M-N"  non-incremental-forward-search-history
             "M-P"  non-incremental-reverse-search-history
             "M-R"  revert-line
             "M-T"  transpose-words
             "M-U"  upcase-word
             "M-Y"  yank-pop
             "M-\"  delete-horizontal-space
             "M-~"  tilde-expand
             "M-C-?"  backward-kill-word
             "M-_"  yank-last-arg

             Emacs Control-X bindings

             "C-XC-G"  abort
             "C-XC-R"  re-read-init-file
             "C-XC-U"  undo
             "C-XC-X"  exchange-point-and-mark
             "C-X("  start-kbd-macro
             "C-X)"  end-kbd-macro
             "C-XE"  call-last-kbd-macro
             "C-XC-?"  backward-kill-line

   VI Mode bindings
             VI Insert Mode functions

             "C-D"  vi-eof-maybe
             "C-H"  backward-delete-char
             "C-I"  complete
             "C-J"  accept-line
             "C-M"  accept-line
             "C-R"  reverse-search-history
             "C-S"  forward-search-history
             "C-T"  transpose-chars
             "C-U"  unix-line-discard
             "C-V"  quoted-insert
             "C-W"  unix-word-rubout
             "C-Y"  yank
             "C-["  vi-movement-mode
             "C-_"  undo
             " " to "~"  self-insert
             "C-?"  backward-delete-char

             VI Command Mode functions

             "C-D"  vi-eof-maybe
             "C-E"  emacs-editing-mode
             "C-G"  abort
             "C-H"  backward-char
             "C-J"  accept-line
             "C-K"  kill-line
             "C-L"  clear-screen
             "C-M"  accept-line
             "C-N"  next-history
             "C-P"  previous-history
             "C-Q"  quoted-insert
             "C-R"  reverse-search-history
             "C-S"  forward-search-history
             "C-T"  transpose-chars
             "C-U"  unix-line-discard
             "C-V"  quoted-insert
             "C-W"  unix-word-rubout
             "C-Y"  yank
             "C-_"  vi-undo
             " "  forward-char
             "#"  insert-comment
             "$"  end-of-line
             "%"  vi-match
             "&"  vi-tilde-expand
             "*"  vi-complete
             "+"  next-history
             ","  vi-char-search
             "-"  previous-history
             "."  vi-redo
             "/"  vi-search
             "0"  beginning-of-line
             "1" to "9"  vi-arg-digit
             ";"  vi-char-search
             "="  vi-complete
             "?"  vi-search
             "A"  vi-append-eol
             "B"  vi-prev-word
             "C"  vi-change-to
             "D"  vi-delete-to
             "E"  vi-end-word
             "F"  vi-char-search
             "G"  vi-fetch-history
             "I"  vi-insert-beg
             "N"  vi-search-again
             "P"  vi-put
             "R"  vi-replace
             "S"  vi-subst
             "T"  vi-char-search
             "U"  revert-line
             "W"  vi-next-word
             "X"  backward-delete-char
             "Y"  vi-yank-to
             "\"  vi-complete
             "^"  vi-first-print
             "_"  vi-yank-arg
             "`"  vi-goto-mark
             "a"  vi-append-mode
             "b"  vi-prev-word
             "c"  vi-change-to
             "d"  vi-delete-to
             "e"  vi-end-word
             "f"  vi-char-search
             "h"  backward-char
             "i"  vi-insertion-mode
             "j"  next-history
             "k"  prev-history
             "l"  forward-char
             "m"  vi-set-mark
             "n"  vi-search-again
             "p"  vi-put
             "r"  vi-change-char
             "s"  vi-subst
             "t"  vi-char-search
             "u"  vi-undo
             "w"  vi-next-word
             "x"  vi-delete
             "y"  vi-yank-to
             "|"  vi-column
             "~"  vi-change-case

SEE ALSO

       The Gnu Readline Library, Brian Fox and Chet Ramey
       The Gnu History Library, Brian Fox and Chet Ramey
       bash(1)

FILES

       ~/.inputrc
              Individual readline initialization file

AUTHORS

       Brian Fox, Free Software Foundation
       bfox@gnu.org

       Chet Ramey, Case Western Reserve University
       chet.ramey@case.edu

BUG REPORTS

       If you find a bug in readline, you should report it.  But first, you should make sure that it really is a
       bug, and that it appears in the latest version of the readline library that you have.

       Once  you  have determined that a bug actually exists, mail a bug report to bug-readline@gnu.org.  If you
       have a fix, you are welcome to mail that as well!  Suggestions and `philosophical'  bug  reports  may  be
       mailed to bug-readline@gnu.org or posted to the Usenet newsgroup gnu.bash.bug.

       Comments and bug reports concerning this manual page should be directed to chet.ramey@case.edu.

BUGS

       It's too big and too slow.

GNU Readline 8.1                                 2020 October 29                                     READLINE(3)