Terminal Multiplexers

authors:

rudi


table of contents


Terminal Muiltiplexers §

Terminal multiplexers are programs that will keep your session running, even if you disconnect from the server. They also allow you to ‘multiplex’ your terminals, spawning multiple shells in one local terminal. The three multiplexers on geosparkies.com are byobu, tmux, and screen.

Byobu §

byobu is the default mutliplexer for geosparkies.com. It was originally designed to provide elegant enhancements to the otherwise functional, plain, practical GNU Screen, for the Ubuntu server distribution. Byobu now includes an enhanced profiles, convenient keybindings, configuration utilities, and toggle-able system status notifications for both the GNU Screen window manager and the more modern Tmux terminal multiplexer, and works on most Linux, BSD, and Mac distributions.

In the spirit of the former tmux page, here is a super basic primer: The basic keys to know are f2, f3, f4, f6, f8, and f9 f2 - spawn new tab f3 - move to previous (left) tab f4 - move to next (right) tab f6 - disconnect from byobu (and the server) f8 - rename a tab f9 - configuration menu (also has a basic help guide)

With those keys, you can do a lot. However tmux shortcuts will work here in byobu (but unless you configure it differently, the escape sequence isn’t ctrl-b, it’s ctrl-a) You can even configure byobu to run automatically when you connect, using byobu-enable (byobu-disable to undo). For a more in depth overview, you can go to byobu’s documentation or man byobu.

Tmux §

Here’s a super basic primer.

to start a new session, type tmux new -s tildemux.

A yellow bar will appear at the bottom of your terminal. You’re now in TMUX!

TMUX has sessions, windows, and panes. Each of these things will have a terminal in it. If you actually typed what I told you to earlier, you’ll be in a session named tildemux. That session has one window, 0. That window has one pane, also named 0. (Computers start counting at 0, not 1.)

windows §

Your tmux bar should look like:

[tildemux] 0:bash*

…which means that you’re in a session named tildemux, which has a window 0, running the command bash. * means that window 0 is active, and the pane running bash is currently active.

To create a new window within this session, type PREFIX c. PREFIX?!? By default, it’s control-b. Now you should see:

[tildemux] 0:bash- 1:bash*

1:bash* means you’re in a pane running bash inside window 1. To change back to pane 0, type PREFIX 0. The * should be back on 0:bash.

Run a cool interactive command, such as htop (to see how many of system resources we’re eating up) or vim (to write some awesome webpages). Your tmux status bar should update to 0:<name of the current process>. So now instead of saying bash it will say htop or vim.

panes §

Panes are great. TMUX panes let you run more than one terminal inside your one, actual terminal. To “split” a new pane, PREFIX ". That makes a horizontal split. You’ll notice there are now two panes open one on top of the other. PREFIX % makes a vertical split, for side-by-side panes. Did I mention that panes are great?

To move between panes in the current window, use PREFIX <up,down,left,right>. That’s right, the arrow keys.

more §

I’m not the best writer or teacher. Just google anything that doesn’t make sense.

Or take a look at this tmux guide

But definitely use tmux or byobu.

Or, if you don’t like it - try screen

screen §

screen is a unix utility that lets you manage multiple shells from within a single window. You switch between them with a few keystrokes. When you disconnect it keeps the processes alive, and you can reconnect from another login.

It’s pretty handy. tmux does a similar set of things.

a nice screen tutorial from ~jonathan will walk you through it.