Spawn agetty manually ?
 

Hello,

as having a bit spare time I'm playing with runit on Slackware. Everything seems to be set correctly however I'm having issues agetty won't open on a specified tty:
just silently dies, without any error message. Launched from a console as root, tty8 is unoccupied.

Can anybody explain above behavior and how to "fix" it ?

Humph, answering my own question.
I've discovered I'd need to run it with setsid as agetty thinks tty is already controlled when launched from an existing session.