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Auto-Updating GNU Screen Window Names

It took a bunch of searching a testing, but I got something that works for me and I like well. Instead of every screen window being called “bash” or being named manually, I now have them all named after the working directory. This is the magic:

PROMPT_COMMAND='echo -ne "\033k$(basename $PWD)\033\\"'

PROMPT_COMMAND gets run every time bash displays a prompt, and those particular escape characters do the magic.

To avoid crap outside of screen, I did this:

case ${TERM} in
export PROMPT_COMMAND='echo -ne "\033k$(basename $PWD)\033\\"'

Which is more general than it needs to be, but maybe I’ll expand it in the future.

Mac OS X, Terminal, Screen, and Ctrl-Arrow Keys

I have had a number of frustrations since I started at Facebook in adapting to the quirks of Mac OS X. I have been in Windows-land for so long that I consider its quirks normal, so figuring out the quirks of OS X has at times been frustrating. Nevertheless, I think I am making good progress.

I am using GNU screen while logged in to linux machines extensively during work, so I invested a little time in setting up a good screenrc. Afterwards, I noticed that I was unable to get the screens to switch using ctrl-left and ctrl-right the same way I would be able to from a Windows machine.

After being frustrated with trying to get Terminal to send the right control characters, and getting screen to recognize them using bindkey, I took a step back and found a solution that actually works. Despite its failings at behaving like PuTTY in every respect, Terminal does offer a lot of customizations, including the ability to change what control characters get sent when you press control-left and control-right, for example. So instead of trying to divine the right bindkey option for Mac OS X (which no one seems to have succeeded at as far as I can tell), I took another approach:

I told Terminal to send “ctrl-a p” (\001ap) for ctrl-left, and “ctrl-a n” (\001n) for ctrl-right. This makes hitting those keys the equivalent of going to the previous and next screens manually, but without the manual part. Of course, if you use a different control character for your screen, you will want to use that instead of ctrl-a as I did, but this finally got screen to behave the way I wanted, which makes me quite happy.

For reference, my screenrc looks like this right now:

vbell off
autodetach on
startup_message off
defscrollback 10000

hardstatus alwayslastline
hardstatus string '%{= kG}%-Lw%{= kW}%50> %n*%f %t%{= kG}%+Lw%< %{= kG}'