Command Line Editing

This chapter describes the optional command line editing feature of Glish. Command line editing is implemented using a modified version of the original editline library. ^14.1(See the editline/README and editline/COPYING distribution files full information.) This library was written by Simmule Turner and Rich Salz, and was modified to work within Glish's asynchronous event constraints.

Command line editing allows you to re-execute previous commands, fix problems with the current command, or search for a previous command matching a particular substring. These operations are performed based on emacs-like control characters and can be used any time you enter a command. Table 14.1 summarizes the editing commands. The notation C-<CHAR> means that the character <CHAR> is typed while the CONTROL key is held down. So C-b is known as control-b. The notation M-<CHAR> means that the META key is held down while <CHAR> is typed or the ESCAPE key is pressed before pressing <CHAR>. So M-b is known as meta-b or escape-b. In addition, BACKSPACE represents the ``backspace key'', DELETE represents the ``delete key'', RETURN analogous to the ``return key'', and UP-ARROW, DOWN-ARROW, LEFT-ARROW, and RIGHT-ARROW analogous to the up, down, left, and right keys common on most keyboards.

These commands become relatively natural with use, and are a great aid when working with the CLI. If you are not interested in all of the control characters, backspace, delete, and the arrow keys perform as expected, and should provide most of what is needed.

Command	Action
`C-p` or UP-ARROW	get the previous command
`C-n` or DOWN-ARROW	get the next command
`C-a`	go to beginning of line
`C-e`	go to end of line
`C-b` or LEFT-ARROW	move back (to the left) one character
`C-f` or RIGHT-ARROW	move forward (to the right) one character
`C-d`	delete the current character. Note `C-d` on an empty line exits Glish.
`C-h` or BACKSPACE or DELETE	delete the previous (to the left) character
`C-k`	kill from the current character to the end of the line
`C-y`	yank back any previously killed character before the current character
`C-l`	redisplay the current line
`C-]` `<CHAR>`	move to the single character `<CHAR>`
`C-t`	transpose current and previous character
`C-r`	search for a string. Enter the string followed by RETURN when prompted with `Search:`. Just pressing return when prompted uses the last search string.
`M-b`	move back (to the left) one word
`M-f`	move forward (to the right) one word
`M-d`	delete from the current position to the end of the word
`M-l`	toggle to lower case from the current position to the end of the current word
`M-u`	toggle to upper case from the current position to the end of the current word
`M-<`	get the first history line
`M->`	get the last history line. This is often used to restart a search.
`M-C-h` or `M-` BACKSPACE or `M-` DELETE,	delete from the current position to the beginning of the current word
`M-w`	copy from the current position to the beginning of the line to the kill buffer for a later yank