I’m continually discovering nifty new features of GNU Screen, and I’ve taken advantage of one of them to fix one of my long-standing annoyances with what’s otherwise a nearly-perfect piece of software – the rather awkward scroll-back buffer.
Here’s a method for essentially using Emacs as the scroll-back buffer (though convenient paste behaviour will have to come later):
First, create a named pipe in your home directory:
Then place the following shell script somewhere in your
$PATH, calling it e.g.
emacsclient -n -t -e '(shell-command "cat ~/.screen.fifo" "*screenfifo*")' &
screen -X eval "hardcopy -h $HOME/.screen.fifo"
screen -X screen -t hardcopy 0 emacsclient -t -e '(switch-to-buffer "*screenfifo*")' -e '(goto-char (point-max))'
Then place the following binding in your
bind E exec read-screen-fifo.sh
Now, pressing your screen prefix key (
C-a by default, back-tick for me) then
E will result in
screen opening an
emacsclient frame containing the entire contents of the initial window’s scroll-back buffer.
Note that commented-out
sleep – if Emacs is a bit slow off the mark reading from the fifo,
screen can get very angry and appear to hang (albeit recoverable by reattaching); so you may want to give it a split-second to catch up. Also, I discovered that
screen is also very picky about what it lets you run inside an
eval, so watch out (hence this all being done with shell scripts). This may be because
screen will refuse to write to the fifo until there’s another program already reading from it – this is different from the behaviour of, say,
screen trick I discovered in the course of this: put
bind R source ~/.screenrc in your
.screenrc to give yourself a way of reloading
screen without the need for a restart (came in very handy when working out the above – I actually managed to completely crash Emacs three times, but Screen only tended to hang, in a recoverable way).