System Startup.

Digital Unix uses a combination of /etc/inittab and the init.d, rcX.d method of system startup.

System startup is initially driven by the /etc/inittab file. Ex:

# OSF/1 Release 1.0 is:3:initdefault:
ss:Ss:wait:/sbin/rc0 shutdown < /dev/console > /dev/console 2>&1
s0:0:wait:/sbin/rc0 off < /dev/console > /dev/console 2>&1
fs:23:wait:/sbin/bcheckrc < /dev/console > /dev/console 2>&1
kls:Ss:sysinit:/sbin/kloadsrv < /dev/console > /dev/console 2>&1
sysconfig:23:wait:/sbin/init.d/autosysconfig start < /dev/console >
/dev/console 2>&1 update:23:wait:/sbin/update > /dev/console 2>&1
it:23:wait:/sbin/it < /dev/console > /dev/console 2>&1
kmk:3:wait:/sbin/kmknod > /dev/console 2>&1 s2:23:wait:/sbin/rc2 <
/dev/console > /dev/console 2>&1 s3:3:wait:/sbin/rc3 < /dev/console
> /dev/console 2>&1 cons:1234:respawn:/usr/sbin/getty console console

From here, process 1 will execute the rc2, and rc3 scripts in sequence. These scripts then run the K scripts with a "stop" parameter, followed by the S scripts with a "start" parameter. These scripts are generally links to scripts that really live in the /sbin/init.d directory.

When the system is put into run level 1, all the K scripts are run with a "stop" parameter, which can be used to gracefully shut the system down.