|  | This is a terse description of the new features added to readline-5.1 since | 
|  | the release of readline-5.0. | 
|  |  | 
|  | 1.  New Features in Readline | 
|  |  | 
|  | a.  The key sequence sent by the keypad `delete' key is now automatically | 
|  | bound to delete-char. | 
|  |  | 
|  | b.  A negative argument to menu-complete now cycles backward through the | 
|  | completion list. | 
|  |  | 
|  | c.  A new bindable readline variable:  bind-tty-special-chars.  If non-zero, | 
|  | readline will bind the terminal special characters to their readline | 
|  | equivalents when it's called (on by default). | 
|  |  | 
|  | d.  New bindable command: vi-rubout.  Saves deleted text for possible | 
|  | reinsertion, as with any vi-mode `text modification' command; `X' is bound | 
|  | to this in vi command mode. | 
|  |  | 
|  | e.  If the rl_completion_query_items is set to a value < 0, readline never | 
|  | asks the user whether or not to view the possible completions. | 
|  |  | 
|  | f.  New application-callable auxiliary function, rl_variable_value, returns | 
|  | a string corresponding to a readline variable's value. | 
|  |  | 
|  | g.  When parsing inputrc files and variable binding commands, the parser | 
|  | strips trailing whitespace from values assigned to boolean variables | 
|  | before checking them. | 
|  |  | 
|  | h.  A new external application-controllable variable that allows the LINES | 
|  | and COLUMNS environment variables to set the window size regardless of | 
|  | what the kernel returns. |