How can I clear scrollback buffer in Tmux?

Terminal Problem Overview

FYI, I am using Tmux through the Mac OS X Terminal app.

Terminal Solutions

Solution 1 - Terminal

This same question has been plaguing me for quite some time. Here's the best I've come up with. Put this into your .tmux.conf file:

bind -n C-k clear-history

This binds ctrl-k to the tmux clear-history command. The -n after bind makes it so you don't have to issue the tmux command prefix (ctrl-b by default). I use bash, so ctrl-l already does the equivalent of typing "clear" at the command line. With these two keys I get a nice ctrl-l, ctrl-k combo, which moves all the scroll buffer off the screen (the "clear") and then deletes all that history (the tmux "clear-history" command).

It's not quite as nice as Terminal's, iTerm's, or Konsole's 1-key combos for clearing it out, but it's a world better than typing in clear-history all the time.

Solution 2 - Terminal

Every answer on here talks about adding new key bindings.

If you just want to do it occasionally you don't need a mapping at all...

Prefix defaults to <Ctrl-b>

Just type <prefix> + : in the relevant pane and then type clear-history and press enter.

If you are on the command line, you can run tmux clear-history in the pane in question for the same effect.

One of the cool things about tmux is that you can just run any of the commands like that... or run them in a shell/script them like tmux command ... or make a keyboard shortcut for them.

Solution 3 - Terminal

As @juanpaco correctly stated, clear-history is the command to clear the scrollback buffer.
I'll add that I like to also clear what's on the screen in the same command. Issuing a send-keys -R resets (clears) the screen, so I use the following in my .tmux.conf

bind-key b send-keys -R \; clear-history

This clears the screen AND the scrollback buffer.

Solution 4 - Terminal

If you want to combine CTRL-L plus clear-history, add this to your ~/.tmux.conf:

bind u send-keys C-l \; run-shell "sleep .3s" \; clear-history

This even works if you're in a MySQL shell for instance.

Solution 5 - Terminal

I found using send-keys -R to be a little slow - here is another way to clear screen and history with a single command

bind-key C send-keys "clear && tmux clear-history" \; send-keys "Enter"

A nested tmux call is used as the more obvious

bind-key C send-keys "clear" \; send-keys "Enter" \; clear-history

fails to clear the screen's current text from the history - the clear-history command appears to run in a separate thread to send-keys.

Solution 6 - Terminal

Found this works best in TMUX 2.6, clearing the screen, scrollback, but keeping the prompt displayed after.

Uses Ctrl-L

bind-key -n C-l send-keys C-l \; send-keys -R \; clear-history

Solution 7 - Terminal

Way simpler than most, I just created a shell script called cls, and run it whenever I want to clear my screen and scrollback buffer.

All it is is this:

cls

clear;
tmux clear-history;

Solution 8 - Terminal

Ctrl-L is used in console applications to redraw the screen. I found that when bound to send-keys -R it would cause the arrow keys to no longer function correctly in some applications (eg vim, mc).

To retain the redraw functionality in console applications, I used:

bind-key -n C-l if-shell -F '#{alternate_on}' 'send-keys C-l' 'send-keys -R C-l; clear-history'

This requires the tmux option alternate-screen to be on (which it is by default).

Solution 9 - Terminal

if you clear your screen with clear, you can check whether TMUX is set, and create an alias accordingly.

put this in your .bashrc:

if [[ $TMUX ]]; then
  alias clear='clear && tmux clear-history'
fi

Solution 10 - Terminal

I've used some of the above plus other sources to come up with:

bind k send-keys C-u \; send-keys C-k \; send-keys " clear && tmux clear-history" \; send-keys "Enter" \; run-shell "sleep .3s" \; send-keys "Up" \; send-keys C-u

The leading space in " clear && tmux clear-history" prevents the command from being written to the history file (providing you have your shell setup to treat leading spaces this way; google "hist ignore space" + the name of your shell for more info). I like to have this command not show up in my history since this is more inline with ctrl-k in the Terminal.

The first send-keys C-u and send-keys C-k will clear whatever is currently typed at the prompt to ensure that the " clear && tmux clear-history" is successful (e.g., if you've typed "ABCDEFG" at the prompt and have your cursor between the D and the E, this ensures that "ABCD clear && tmux clear-historyEFG" is not sent to the shell, which would fail).

The send-keys "Up" and last send-keys C-u clears out the last items from your shells internal history. Even with the trailing space mentioned above the internal history of the shell will include the " clear ..." line. Sending up and Ctrl-u gets rid of this.

Lastly, in iTerm I set ctrl-k to map to ctrl-a k (I have my tmux prefix set to ctrl-a), so I can type ctrl-k which is what my hands want to do from so many years of doing so. I do this, by going to iTerm > Preferences > Profiles > Keys and adding a shortcut to send the hex code "0x01 0x6B". There's a great article here which gives more info on using hex codes with tmux and iTerm: http://tangledhelix.com/blog/2012/04/28/iterm2-keymaps-for-tmux/

That pretty much gives me ctrl-k with tmux. The only thing that still kinda nags at me is that the real ctrl-k without tmux doesn't have problems if you currently have something typed at the prompt and will preserve what you've typed while clearing the screen. As mentioned, this approach needs to clear what's typed so the " clear ..." command doesn't fail. But it's pretty damn close!

Solution 11 - Terminal

For a quick fix to clear individual tmux panes you could set up an alias...

# Tmux Clear pane
alias tc='clear; tmux clear-history; clear'

Solution 12 - Terminal

So, I've been using plu's approach from above for a while, but I got fed-up with the limitations thereof (basically, the ⌃L passed through is meaningless unless piped to a program that understands it.)

So I've improved upon the various approaches in different answers to this thread; although complex, this approach works with both shells and other commands:

# ⌃K: Clears the current pane (from <https://stackoverflow.com/a/34162098>)
bind-key -n C-k \
   if-shell "test \"$(printf '#{pane_current_command}' | tail -c 2)\" = sh" \
      "send-keys C-l ; run-shell 'sleep .3s' ; clear-history" \
      "split-window -vp 100 ; clear-history -t ! ; kill-pane"

Try it with tail -f /private/var/log/system.log or something!

Caveats:

There's one important note here: this is invisibly resizing the pane being cleared, if it's not a shell. This can trigger resizing behaviour in some command-line applications listening for SIGWINCHes; but my reasoning is that this isn't a big problem, because those are programs you're very likely not going to be trying to ‘clear’ anyway.

In addition, the shell-quoting situation is already a mess, and can easily become more of one when embedding #{pane_current_command}, so be careful, you may have to modify this based on your default-command setting.

The same applies to my testing of the end of that command matching "sh"; if you have a default-command of something like /bin/bash --login or something complicated involving exec, the actual command may not end with "sh"; use ⌃B : to execute display-message '#{pane_current_command}' if you want to see what is being tested against.

Solution 13 - Terminal

After a lot of research and spending time. I have found the best way for me on zsh and terminal.app

I am using prefix-c to clear the screen and prefix-C to clear the history and the scroll buffer and leaving no lines above because I find it annoying.

#Without Vim

# clear screen
bind c send-keys 'C-l'
# clear screen and history
bind C send-keys -R \; send-keys C-l \; clear-history \; send-keys

#With Vim

# check if the pane is running vim
is_vim="ps -o state= -o comm= -t '#{pane_tty}' \ | grep -iqE '^[^TXZ ]+ +(\\S+\\/)?g?(view|n?vim?x?)(diff)?$'"

# clear screen
bind c if-shell "$is_vim" "send-keys c" "send-keys 'C-l'"
# clear screen and history
bind C send-keys -R \; send-keys C-l \; clear-history \; send-keys

Solution 14 - Terminal

why not? bind -n C-l send-keys C-l

Solution 15 - Terminal

If you want a complete pane clearing, another option is to temporarily resize the pane to one line, clear the history, then resize it back. This should work possibly flicker-free with one tmux chain of commands. The advantage is that it works regardless of what program is running in the pane. Of course this makes the shell script logic a bit more complicated.

bind-key -n F11 run "
    if [[ #{window_panes} == "1" ]] ; then
  	    tmux send-keys C-l; sleep 0.1 ; tmux clear-history ;
    else
	    restored_height=$((#{pane_height} + #{pane_at_bottom}));
	    tmux resize-pane -y 1 \\; clear-history \\; resize-pane -y \${restored_height} ;
    fi
"

Content Type	Original Author	Original Content on Stackoverflow
Question	Daya Sharma	View Question on Stackoverflow
Solution 1 - Terminal	juanpaco	View Answer on Stackoverflow
Solution 2 - Terminal	JonnyRaa	View Answer on Stackoverflow
Solution 3 - Terminal	Mark Bolusmjak	View Answer on Stackoverflow
Solution 4 - Terminal	plu	View Answer on Stackoverflow
Solution 5 - Terminal	cage433	View Answer on Stackoverflow
Solution 6 - Terminal	ideasman42	View Answer on Stackoverflow
Solution 7 - Terminal	Brad Parks	View Answer on Stackoverflow
Solution 8 - Terminal	Phil	View Answer on Stackoverflow
Solution 9 - Terminal	Galarmo	View Answer on Stackoverflow
Solution 10 - Terminal	Brett	View Answer on Stackoverflow
Solution 11 - Terminal	Paul Hale	View Answer on Stackoverflow
Solution 12 - Terminal	ELLIOTTCABLE	View Answer on Stackoverflow
Solution 13 - Terminal	Rahul Katariya	View Answer on Stackoverflow
Solution 14 - Terminal	klebervirgilio	View Answer on Stackoverflow
Solution 15 - Terminal	Dan Aloni	View Answer on Stackoverflow