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Comment by grive | Hacker News Reader

In readline, ^U will only clear from the cursor to the start of the line, leaving anything on the right. ^K is the converse.

I'm not sure you are speaking about readline though.

Another very useful thing I use daily is Alt-F/B, to move forward/backward in the line one word at a time. Control does the same, one letter at a time. D will delete an element instead.

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There's a lot of unexpected gems in the readline defaults. I recommend people try paging through "bind -p" in bash some time to see what's there.

Personal favorites are C-r to search back in history and C-x C-e to edit the current command line in an external editor.

Emacs users will recognize many of the readline defaults -- unsurprisingly, given both are GNU software.

I use "yank-last-arg" most often, which is M-. by default.

  $ mkdir abcd
  $ cd <M-.>

On Zsh, I have M-, bound to "copy-earlier-word", which makes M-. M-, M-, cycle through the arguments to the previous command.

In reading the manpage for Bash, which doesn't have this function, I've just found "history-search-backward", which searches through history to find commands based on what you've already typed. That will come in useful!

  $ bind '"\er":history-search-backward'
  $ bind <M-r>

(Note that M-r is bound to "revert-line" by default, but I doubt I'll use that.)

These functions are all listed, with explanations, in the Bash and Zsh manpages.

Edit: As I see from another comment, a binding for "history-search-backward" to the Page Up key is in /etc/inputrc on Debian and derivatives.

It is also very convenient to remap up/down keys to not just list history, but to do completion based on already typed characters:

    if [[ $- == *i* ]]
    then
        bind '"\e[A": history-search-backward'
        bind '"\e[B": history-search-forward'
    fi

(fix: grammar)

Debian and Ubuntu typically have a commented-out mapping for this in /etc/inputrc as pgup/pgdn that I always enable in my ~/.inputrc. Editline supports something similar in .editrc IIRC.

Funny, I became FreeBSD user because default .cshrc contained it (iirc). I didn't know about shells, readline, etc. back then. Wonder why they do not enable it on up-down by default, cause I see too many linuxoids around bored with up-up-up-enter up-up-up-enter to replay history, not even knowing that completion exists (along with at least ^K ^U ^C).

What's the point to type a half-command and then replace input line with one from history if I press up? That somewhat resembles ugly cmd.exe, which every windows user imagines when someone says 'cli'.

Weird, I'd have thought C-r is the one readline command everybody knows even if they know nothing else abour readline. Almost cannot imagine using command line without it. (Though there's also the "like tab-complete but from history" that I never really learned to use.)

Ah! yes, at this point C-r is so entrenched in my habit, I didnt even realize it might be new to some.

This is the shortcut to first learn when starting living in the command line.

Yes some of these useful functions should be bound by default IMHO. Here are my settings to bind ctrl-{left,right} and {up,down} to more useful defaults. I.E. jump as the shell tokenizes the line, and search history for what's already typed respectively

For the vi-adherents out there, `set -o vi` will let you navigate your prompt and history with vi-like keybindings. I'm amazed by how many vi users don't know this.

I'm amazed by how many people still run bash!

Why wouldn't they it is one of the defacto standards? You use what you know most of the time.

¯\_(ツ)_/¯

To add to that, C-P will go up in your history and C-N down. It is extra useful when using GDB in TUI mode (which is activated using C-x,a), which will capture your UP/DOWN arrow to navigate the source...

Actually, just go read http://ss64.com/bash/syntax-keyboard.html or something, once per day, integrate a new one each time, and you will improve your productivity on the command line (as well as comfort).

For gdb TUI, you can also use the 'focus cmd' and 'focus src' commands to choose which window gets to handle up/down. I usually keep the command window focused out of habit because the source window intercepts too many keys for my liking.

Nice link - reminds me to try to use the history stuff like ! and ^ more.

I also find Ctrl-W for backspacing a word at a time useful and also Ctrl-A/E for jumping to the beginning and end of the current line.

Ctrl-L to clear the screen except the current line is also somewhat useful if you're at the bottom of the terminal screen and editing a long command line.

Somewhat less useful but neat is Alt-U which will cause the current word under the cursor to become all upper case and Alt-C which is similar but changes the first letter to upper case and the rest of the word to lower case.

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