This is for SCO; for Linux, see How to use multiple consoles in Single User mode (Linux)
(From a newsgroup post by John Dubois):
You can go to init state 4 by doing "init 4". This leaves all of the console ttys enabled for login, while not running the rc2 scripts that start up remote services. Note that after the init state transition you won't be logged in anywhere; you will need to log in on each screen that you want to use. Also,
if you have any serial/modem lines that are enabled for login, you should remove the "4" from the 2nd field of their inittab lines in /etc/inittab and the appropriate file under /etc/conf/init.d, so that no one will be able to log in on those lines while you're in init state 4. When you want to go multiuser, first go back to init state 1 (single-user mode) with "init 1"; then go multiuser (state 2). If you try going straight from state 4 to state 2, some rc scripts are liable to be confused.
John DuBois email@example.com KC6QKZ/AE https://www.armory.com/~spcecdt/
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