Miscellaneous Commands

Several miscellaneous commands complete emacs editing mode; they are shown in Table 2-6.

Table 2-6. emacs-mode miscellaneous commands

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Command

Description

CTRL-J

Same as RETURN

CTRL-L

Clears the screen, placing the current line at the top of the screen

CTRL-M

Same as RETURN

CTRL-O

Same as RETURN, then display next line in command history

CTRL-T

Transpose two characters on either side of point and move point forward by one

CTRL-U

Kills the line from the beginning to point

CTRL-V

Quoted insert

CTRL-[

Same as ESC (most keyboards)

ESC-C

Capitalize word after point

ESC-U

Change word after point to all capital letters

ESC-L

Change word after point to all lowercase letters

ESC-.

Insert last word in previous command line after point

ESC-_

Same as ESC-.

BSD-derived systems use CTRL-V and CTRL-W as default settings for the "quote next character" and "word erase" terminal interface functions, respectively.

A few of these miscellaneous commands are worth discussing, even though they may not be among the most useful emacs-mode commands.

CTRL-O is useful for repeating a sequence of commands you have already entered. Just go back to the first command in the sequence and press CTRL-O instead of RETURN. This will execute the command and bring up the next command in the history list. Press CTRL-O again to enter this command and bring up the next one. Repeat this until you see the last command in the sequence; then just hit RETURN.

Of the case-changing commands, ESC-L is useful when you hit the CAPS LOCK key by accident and don't notice it immediately. Since all-caps words aren't used too often in the UNIX world, you probably won't use ESC-U very often.

CTRL-V will cause the next character you type to appear in the command line as is; i.e., if it is an editing command (or an otherwise special character like CTRL-D), it will be stripped of its special meaning.

If it seems like there are too many synonyms for RETURN, bear in mind that CTRL-M is actually the same (ASCII) character as RETURN, and that CTRL-J is actually the same as LINEFEED, which UNIX usually accepts in lieu of RETURN anyway.

ESC-. and ESC-_ are useful if you want to run several commands on a given file. The usual UNIX convention is that a filename is the last argument to a command. Therefore you can save typing by just entering each command followed by SPACE and then typing ESC-. or ESC-_. For example, say you want to examine a file using more, so you type:

$ more myfilewithaverylongname

Then you decide you want to print it, so you type the print command lp. You can avoid typing the very long name by typing lp followed by a space and then ESC-. or ESC-_; bash will insert myfilewithaverylongname for you.

 

[3] Not available in versions of bash prior to 2.05a.

[4] emacs users will recognize this as minibuffer completion.