How to actually type CTRL-A in a linux terminal?

Question

How do I to invoke Ctrl-a in a Linux terminal session. I am trying to share a screen using screen.

The command to turn on multiuser is Ctrl-A :multiuser on , I know how to press Ctrl+a on my keyboard but what is the command line version of Ctrl-a?

How would I type Ctrl-A :multiuser on, without Linux telling that the command is not found?

Solution 1

Since you're in a screen session, press Ctrl+A and press A again.

Solution 2

I knew you could send commands from within a screen session to the screen. So from the man page:

  -X   Send the specified command to a running screen  session.  You  can
        use  the  -d or -r option to tell screen to look only for attached
        or detached screen sessions. Note that this command  doesn't  work
        if the session is password protected.

this leads to:

screen -X multiuser on

Invoking this from within your screen should do the job. Could not test it myself right now.