[desktop-discuss] Shutdown in JDS and init 5

[David Bustos]

Quoth Dick Hoogendijk on Fri, Jun 15, 2007 at 08:59:34PM +0200:
> Alan Coopersmith <alan.coopersmith at sun.com> writes:
> > For power off it appears to do:
> > 	/*
> > 	 * Send SIGPWR signal to the init process to shut down the system.
> > 	 */
> > 	if (kill (1, SIGPWR) == -1)
> > 		uadmin(A_SHUTDOWN, AD_POWEROFF, 0);
> 
> >From man uadmin:
> 
> WARNINGS
>      On x86 systems, shutting down the system by means of  uadmin
>      does  not  update the boot archive. Avoid using this command
>      after  manual  editing  of  files  such  as  /etc/system  or
>      driver.conf(4).
> 
> So I guess, init 5 _is_ safer.

Well uadmin() shouldn't destroy any of your data, but the system won't
come up cleanly if you've changed boot-archive configuration, which is
pretty rare.  But note that the code only calls uadmin() if the kill()
fails.  Though I don't think that kill() is quite correct, since SIGPWR
instructs init that the power has failed and the UPS will cut off power
soon.


David