AIPS HELP file for READLINE in 31DEC22
As of Sat Sep 23 12:42:38 2023
Type: GNU readline is a user-input interface for AIPS under UNIX.
Use: The GNU readline library is now used to handle user input under
the following UNIX and UNIX-like operating systems:
OSF/1 (a.k.a. Digital UNIX)
The GNU readline library gives the user the ability to use the
cursor-arrow keys, as well as various "control" and "escape"
key-sequences, to recall previously-entered commands, edit the
current command-line (without having to back-space and re-type
the entire line), search the command history for
previously-executed commands, define customized key-bindings for
executing commands and macros, etc. The full information may be
obtained with the command 'man readline' from the system
command-line (not inside AIPS). There is also "tab completion"
based on the list of AIPS help files and on context. At any
point, when typing a symbol, you may hit the TAB key. The symbol
name will be completed if it is unique or the screen will flash
(or the bell sound) if it is not. A second hit on the TAB key
will produce a list of possible completions. Since a task name
cannot be the first symbol on a line, tasks are included in the
possible completions only after some other symbol appears on the
The default key-bindings should be very familiar to users of
Emacs and/or the bash shell; many of them should also be
recognizable to users of the Korn and tcsh shells. Hard-core vi
users can put AIPS into "vi-mode" and use vi-like key-bindings
instead. (The basic Emacs-like key-bindings will be outlined
below; it will be assumed that those who are using the
non-default vi-like key-bindings already know what they are
Also, the user's command-line history is automatically saved
between sessions, unique to both the user and the "AIPS number"
of the session, and then recovered at the next AIPS startup.
Use of the GNU readline library for input can be disabled on a
per-session basis by starting AIPS with the "norl" option. This
can prevent problems under some operating systems (most notably
HP/UX) with putting AIPS into the background, when running with
input "fed" from a script, or when debugging AIPS itself.
Key-sequences/bindings using the CONTROL key will be prefixed
below with "C-".
Those using the ESCAPE key (or "META" key--often available as the
ALT key on PC keyboards and as the "diamond" key on Sun
keyboards) will be prefixed with "M-".
The basic cursor-movement key-bindings are:
C-b backward-character [also: left-arrow]
C-f forward-character [also: right-arrow]
C-p previous-command (in history list) [also: up-arrow]
C-n next-command (in history list) [also: down-arrow]
C-r incremental-search (backward through history list)
M-< beginning-of-history (first command in history list)
M-> end-of-history (last command in history list)
The basic editing key-bindings are:
C-d delete-character (under cursor)
M-d delete-word (to right of cursor)
M-DEL delete-word (to left of cursor)
C-t transpose-characters (left with under cursor)
(DELETE and BACKSPACE work as expected.)