Setting Up tmate

Before you continue, read about what is a terminal.

Make sure you have set up apt if you use WSL and brew if you use macOS.

What is tmate?

tmate is a tool that allows you to share your terminal with others. This allows another person to have enter text into your terminal and to see the output returned by your terminal.

We will use tmate to allow tutors to view and type into your terminal.

Giving someone else full control of your computer is dangerous -- so you need to be sure that you are sharing your terminal with someone you trust (e.g., your professor and your tutor). Do NOT share your tmate link publicly.

Installing tmate on WSL or Ubuntu

Run the following in your terminal:

sudo apt install tmate

Installing tmate on macOS

Run the following in your terminal:

brew install tmate

Running tmate

To share your screen with someone you trust, run:

tmate

You should then see the following messages (or something similar):

Tip: if you wish to use tmate only for remote access, run: tmate -F        [0/0]
To see the following messages again, run in a tmate session: tmate show-messages
Press <q> or <ctrl-c> to continue
---------------------------------------------------------------------
Connecting to ssh.tmate.io...
Note: clear your terminal before sharing readonly access
web session read only: https://tmate.io/t/ro-Zv6kbZxwLtc84NXnnFJtGvnYE
ssh session read only: ssh ro-Zv6kbZxwLtc84NXnnFJtGvnYE@sgp1.tmate.io
web session: https://tmate.io/t/3svwMBrjhwgp93QmZFHLnwzRP
ssh session: ssh 3svwMBrjhwgp93QmZFHLnwzRP@sgp1.tmate.io

Note that your output will not be exactly the same as the above, particular, the seemingly gibberish text is randomly generated when you run tmate, so it will be a different gibberish every time. Further, tmate 2.2.1 provides fewer options and has a shorter message.

There are several important piece of information here:

There are a list of links for you to share with your tutors. Suppose your tutor wants to see (but not control) your screen through a web browser, you can send the link marked as web session read only: to him or her (e.g., via private chat in Zoom). If your tutor needs to show you something on your shell through a web browser, you can send the link marked as web session: to him or her. (In the example above: send https://tmate.io/t/3svwMBrjhwgp93QmZFHLnwzRP)

If you do not copy down the links and need to access them later, just run tmate show-messages.

Note that the links are randomly generated and are different every time you run tmate.

Once you have copied and send the link to your tutor, press Q or Ctrl+C to continue. Your terminal is now shared with your tutor. You can tell this as there is a small bar at the bottom of your terminal's screen.

To stop sharing, hit Ctrl+D at the command prompt¹.

Here is a small screencast to demonstrate this: