✅ Copy All only copying screen in Tmux mode

[hulleyrob]

In a Tmux connection if I select copy screen or copy all I get the same clipboard information. (69 lines)

However if I do the following:
CTRL+B + :
capture-pane -S -10000 + Return
CTRL+B + :
save-buffer /home/{user}/filename.txt + Return

and then check how many lines:
wc -l /home/{user}/filename.txt

I get 9187 lines.

I think there may be a bug with copy all.

Thanks
Rob

[isontheline]

Hi Rob,

Thanks for the detailed report. This is actually expected behaviour rather than a bug, and here is why.

When you attach to tmux, it switches the terminal to the alternate screen buffer and redraws the visible screen itself. The scrollback history lives inside tmux, on the server: it is never sent to WebSSH. All WebSSH ever receives is the current screen, so in a tmux session "Copy All" and "Copy Screen" necessarily return the same content. WebSSH cannot copy data it never received.

That is also why capture-pane -S -10000 gives you 9187 lines: you are asking tmux directly, and tmux is the only one that has them.

The same applies to any terminal emulator, and to any full-screen program using the alternate buffer (vim, less, htop, screen…).

If you want tmux history in your device clipboard, the right path is through tmux itself:

• set -g set-clipboard on in your ~/.tmux.conf: anything you copy in tmux copy mode (CTRL+B then [) is pushed to the local clipboard through OSC 52, which WebSSH supports (it asks for your confirmation by default).
• Or keep using capture-pane + save-buffer as you did, which is the most reliable way to dump a very large history.

Outside tmux, "Copy All" does include the whole WebSSH scrollback.

I'm closing this as "not a bug", but feel free to comment if something is still unclear.

Arnaud

[hulleyrob]

Sorry one more Q is there a reason why there is no show all line buffer option on Mac but is on iPad/iPhone?

Its dead easy to copy and paste from that what I want while in a TMUX session without messing with "CTRL+B [" and swapping modes.

[isontheline]

Just maintain OPTION key while you make your selection in order to bypass tmux selection handler

[hulleyrob]

Ah ok thank didnt realise I could do that either this has been a learning curve!

Thanks

[hulleyrob]

Is there a way to do that and scroll off screen?

[isontheline]

Ah ok thank didnt realise I could do that either this has been a learning curve!

No problem you're welcome Rob!

Is there a way to do that and scroll off screen?

Unfortunately no I'm sorry, or at least the answer is on the tmux side as WebSSH doesn't know which app is running on the remote side