I just use tmux's native copy/paste mechanism, using the keyboard. Using that it's possible to get the full scrollback buffer, or any part of it.

And I want to paste it into a non-terminal application running locally while the tmux is on a remote host?

You can always use ssh and something like xclip or pbcopy.

Also, I always use mosh for ssh (when possible) so that I can recover my connection if I run into network issues. Since mosh works by synchronizing a virtual screen, I don't get scrollback at all without tmux or the like.

I just added a feature to tmux-git that makes the tmux clipboard propagate up into higher clipboards for nested tmux. https://github.com/tmux/tmux/commit/4ede35c48c089abe3fca0d94...

Keep in mind that your terminfo has to support this, so make sure your ncurses-term package is the latest release from Jan 28.

I also made a patch for st to support OSC 52 propagation into Xorg, but it was rejected by the st maintainers because it uses base64 (as the OSC de-facto spec from xterm dictates).

The patch for st is however in a branch of the Wayland-fork of st

https://github.com/michaelforney/st/tree/selection

Another option if you use nested copies of tmux is to use this feature to get the remote clipboard into the local one, then yank with xclip.

This. I like terminal scrollback but it's gone for me.

'xclip -selection clipboard' works fine for this use case.

[Edit] Assuming you have SSH configured to forward to your local X server [0].

[0] http://unix.stackexchange.com/a/16697

Unfortunately many ssh servers gratuitously disallow X11 forwarding; tcp forwarding can accomplish the same, but then setting up DISPLAY &ct. need to be done manually.

In the latest git builds of tmux (with the latest terminfo db from ncurses), you can have clipboards propagate from remote tmux to local tmux (nested configuration) using the new OSC52 control sequence implemented in a patch from 2 weeks ago.

Also, if your terminal emulator (rxvt, xterm on Linux and mintty on Windows) support OSC52 escape sequences for clipboard setting, this means you don't need X11 forwarding anymore, since you can set your X11 clipboard from tmux.

If anyone can help me get in touch with the libvte people, I want to patch OSC 52 support in there as well, since this is a great feature that should _not_ be relying on X11 forwarding or whatever.

I know that there is an option for integrating tmux's internal clipboard with X11's but I haven't bothered with them because I prefer to keep the clipboards of the various terminal apps I use separate.

It depends ultimately on the terminal to support it though. Only Linux terminals that support it atm are xterm and (u)rxvt, and there is an out-of-tree patch for st that I made (though it was rejected for being too long (around 40 lines).

And it's slow.