KnowledgeBase 00084: Command Editor
This article was originally published as a
Tip of the Week.
Introduction
The command editor records the most recent commands executed by a user from the
command prompt. By default, 99 commands are stored but this can be altered
using the CMDSTACK configuration parameter.
Two styles of command editor are provided; one based on the "dot commands"
found in many multivalue environments, the other using the cursor and
control keys.
The Dot Commands
Except where stated below, the value of n defaults to 1 if ommitted.
| .An text |
Append text to command stack entry n. There must be a space
before text. Any additional spaces will be included in the appended
data. |
| .Cn/old/new/G |
Change string old to
new in stack entry n.
The optional G causes a global replacement where all occurrences of old
are replaced by new. If G is not specified, only the first occurrence of
old is changed. |
| .Dn |
Delete stack entry n. |
| .In text |
Insert text as entry n. There must be a space before
text. Any additional spaces will form part of the inserted entry.
|
| .Ln |
List the most recent n commands. The value of n defaults
to 20. |
| .Rn |
Recall (copy) entry n to position 1 without deleting the original
copy. |
| .Un |
Convert entry n to upper case. |
| .Xn |
Execute command n. The repeated command is copied to position 1
except when executing the current most recent command. |
| .? |
Display a help message regarding the stack manipulation commands. |
There are additional dot commands described in the QM Reference Manual.
Using Cursor and Control Keys
| Ctrl-A or HOME | Move cursor to start of command. |
| Ctrl-B or Cursor Left | Move cursor left one place. |
| Ctrl-D or DELETE | Delete character under cursor. |
| Ctrl-E or END | Move cursor to end of command. |
| Ctrl-F or Cursor Right | Move cursor right one place. |
| Ctrl-G | Exit from the command stack and return to a clear command line. |
| Ctrl-K | Delete all to the right of the cursor. |
| Ctrl-N or Cursor Down | Display "next" command from command stack. |
| Ctrl-O or Insert | Toggle insert/overlay mode. |
| Ctrl-P | Display "previous" command from command stack. |
| Ctrl-R | Search back up the command stack for a given string. The string may be entered either before or after the Ctrl-R. Using Ctrl-R again, finds the next item matching the supplied string. |
| Ctrl-T | Interchange characters before cursor. |
| Ctrl-U | Convert command to uppercase. |
| Ctrl-Z or Cursor Up | Display "previous" command from command stack. |
| Backspace | Backspace one place. |
Configuring the Command Editor
Field 3 of the $RELEASE record in the VOC file can be used to control the
behaviour of the command editor. The following uppercase letters may be
present:
| E | Position the cursor at the end of a recalled command rather than the start. |
| L | Use screen size to determine default number of items in .L command. |
| O | Start in overlay mode. |
| S | Show the stack commands when moving back through the stack. |
| X | Clear the recalled command if the first character typed is not a control code. This mode cannot be used with E. |
Related Articles
None.
