On 06/17/2016 08:54 AM, Edward Bartolo wrote:
[snip]
> PID 1 should fork only once to run the first script that loads the
> operating system. Once execution enters the infinite loop there is no
> way of it jumping to somewhere else. Therefore, only one child is
> forked. This child should terminate on as soon as the OS loading
> script terminates. On my system it behaves that way. Forking children
> indefinitely in absolutely NOT minimal and is highly undesired
> considering this should be minimal.

Thanks for the explanation. And I understand that the script is purely
for pedagogical purposes. It works well as an educational demo since it
is short and uncomplicated. I appreciate it. I think it has helped my
understanding of how things can work.

The part I am wondering about has to do with what kind of model actual
sysvinit follows. In regular devuan, I see that my daemons are children
of PID 1 which is /sbin/init. So, if I may guess, it looks like init
forks once for each daemon. Then each fork then execs (eventually or
directly) one of the init scripts in /etc/rc.?/ which uses
/sbin/start-stop-daemon to exec the daemon itself. Thus through the
cascade of execs, the daemon inherits the PID of the fork and the PPID
of init. Is that more or less what sysvinit is doing?

Regards,
Lars