Screen -- set up your project's terminal environment once and only once.

by Miles Matthias

With any project, I'm running several programs at once during the development process. This usually results in several tabs in the Terminal app - one for my local server, one for my database, one for my client application, and one for git. (Right now I use a GUI editor (ST2), but I may be reverting to vim soon...) This multiple tab setup re-occurs for each project I'm working on, and I'm usually switching between multiple projects several times a day.

With this multi-tab setup, when I have to switch the project that I'm working on, I have to either open a new Terminal window with its own tabs for that project and deal with having a more than required number of windows open (not an option for a minimalist like myself) or close all of the tabs I have open, only to re-open them all when I switch back to that project.

Well like most days, I learned a clever solution to this problem from the dojo4 wise and all-powerful leader, Ara. He uses the GNU Screen program. Within a single Terminal tab, Screen allows you to open multiple "windows" (aka tabs) within the same Terminal tab. Here's how to use it:

# creating and reattaching to a session
screen -S [name] = create a named screen
screen -D -R [name] = reattach to a named screen and detach other people if nec
screen -list = list screens

# (exiting all windows in a screen session will exit that session. However a screen session is a running process, so you can kill it manually.)

# within a screen session:
ctrl-A + ? = help
ctrl-A + " = list windows
ctrl-A + c = create new window
ctrl-A + n = next window
ctrl-A + p = previous window
ctrl-A + A = rename a window

# aliases we use
alias sl='screen -list '
alias sdr='screen -d -r '
alias s='screen -D -R '
alias ss='screen -S'

sdr [name] = reattach to a named screen and detach other people if nec
ss [name] = create a named screen
sl = list screens

Another really cool feature of screen is that when you detach from a screen session, all of your windows remain running, and when you re-attach to the screen session, you have all of your windows back at your disposal.

When we discussed this in our office, Ryan Cook created a nice little Ruby helper to create screen sessions that are named after your current directory.

So my workflow has changed from having multiple tabs in Terminal open to a single tab in Terminal where I re-connect to a screen session for each project I'm working on. That allows me to switch projects extremely quickly and to stop wasting time re-setting up and re-tearing down all of the Terminal tabs I'm using for a project.

Now I just have to convert more things to terminal usage (like my editor) in order to really make the most of screen...