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It seems that clear and bash Ctrl-L are quite different; clear completely removes all previous terminal information (so you cannot scroll up) while Ctrl-L just scrolls the screen so that the cursor is at the top of the page so that you can still scroll up and see previous information. I much prefer the Ctrl-L system. Is there a way to override clear so that it does a Ctrl-L instead of wiping all previous terminal information? This is not a huge issue, but I'm just wondering out of curiosity if there is a way to alias clear to point at my preferred Ctrl-L functionality.

As a side note, I just noticed that PowerShell also has a binding for Ctrl-L and it performs the same way as Ctrl-L on bash; it seems that the PowerShell designers there took a lot from bash, while cmd.exe consoles do not have this functionality.

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    See this. Commented Oct 26, 2021 at 7:51
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    Ah, that's great, as simple as doing clear -x, I should have noticed that before ... 🤔 Thanks. Commented Oct 26, 2021 at 8:22
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    I really dont understand why clear -x isnt just clears default behaviour, and then you could wipe out the history with some customized option. Commented Oct 26, 2021 at 9:50
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    Indeed, I agree, that's actually quite strange. "What happened before" is of general interest to almost every person that works on a terminal. Blasting that away in the brutal way that the default behaviour of clear does is hard to justify. I think I will put alias clear='clear -x' into my .bashrc and if I somehow ever want to destroy all session information, I can use \clear or create alias brutally-delete-everything='\clear' 😉 Commented Oct 26, 2021 at 9:55
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    alias cl='printf "\e[H\e[2J"' also does the job. Commented Oct 28, 2021 at 4:23

2 Answers 2

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Is there a way to override clear so that it does a Ctrl-L instead of wiping all previous terminal information?

alias clear='tput -x clear'

Yes, Ctrl-L in bash (while in set -o emacs mode) does exactly the same thing.

Or you can just hardwire the escape with alias clear='printf "\033[H\033[2J"' which should work in most terminal emulators, and does not assume that you have ncurses or bash installed.

NB: the clear applet from busybox does NOT wipe off the scrollback buffer, so you don't have to do anything special if you're using some busybox-based system, as most embedded Linux systems are.

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  • Very interesting. Is there a guide somewhere to the escape codes that you used here? "\033[H\033[2J"'. I only use colour codes, I'd be curious to see what else they can do? Commented Oct 26, 2021 at 18:46
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    @YorSubs: The portable method is to use tput with the names listed in terminfo(5) (type man 5 terminfo and scroll down until you get to the big table; the possible arguments to tput are listed under Cap-name). This assumes your TERM environment variable is set correctly, which it should be unless your bashrc is mucking with it (don't do that!). Note that the string capabilities are generally the most interesting/useful. Commented Oct 26, 2021 at 20:58
  • In 2024, my Mac version of tput (from ncurses version 5.7 (patch 20081102)) does not have the -x option to tell it to not clear the scrollback. But, a plain tput clear does work for me to clear the screen without clearing the scrollback. So, I added this to my .bash_aliases file - alias clear='tput clear' and that fixed it for me. Commented Apr 12, 2024 at 18:06
  • The version of the alias with the raw control codes worked for me too (2024, Mac, iTerm, brew-installed tmux). Commented Apr 12, 2024 at 18:07
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clear is a terminal command, excerpt of man clear:

DESCRIPTION clear clears your screen if this is possible, including its scrollback buffer (if the extended “E3” capability is defined). clear looks in the environment for the terminal type given by the environment variable TERM, and then in the terminfo database to determine how to clear the screen. clear writes to the standard output. You can redirect the standard output to a file (which prevents clear from actually clearing the screen), and later cat the file to the screen, clearing it at that point.

Ctrl+l is a keybinding to readline's clear-screen command (man 3 readline).

Clear the screen, then redraw the current line, leaving the current line at the top of the screen. With an argument, refresh the current line without clearing the screen.

I can't find a way to alias clear to the readline clear-screen command, and it may not be possible at all.

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  • Worst case you can do something like bind '"clear\n": clear-screen' Commented Oct 27, 2021 at 2:38
  • @zevzek why not? Commented Oct 28, 2021 at 4:20
  • clear -x behaves like ctrl+l for me on Ubuntu. Commented Dec 24, 2022 at 5:39

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