On Wed, Jul 04, 2012 at 11:00:53PM +0200, Paul Menzel wrote: > Am Mittwoch, den 04.07.2012, 21:33 +0100 schrieb Roger Leigh: > > On Wed, Jul 04, 2012 at 10:17:10PM +0200, Paul Menzel wrote: > > > > > > the manual of `update-rc.d` contains the following paragraph. > > > > > > $ man update-rc.d > > > […] > > > When invoked with the remove option, update-rc.d removes any > > > links in the /etc/rcrunlevel.d directories to the > > > script /etc/init.d/name. The script must have been deleted > > > already. If the script is still present then update-rc.d aborts > > > with an error message. > > > […] > > > > This is my understanding. It should only remove the links if you use > > "-f remove" to force removal.
I'm not entirely certain of the historical reasons, but it's likely a safety feature to prevent accidental removal of links, since you could make your system unbootable if you removed a critical link. > > > It looks like `update-rc.d remove name` still works though when the > > > script in `/etc/init.d/name` is not removed beforehand. > > > > > > $ sudo update-rc.d pulseaudio remove > > > update-rc.d: using dependency based boot sequencing > > > $ ls -l /etc/init.d/pulseaudio > > > -rwxr-xr-x 1 root root 2227 1. Okt 2011 /etc/init.d/pulseaudio > > > $ ls -l /etc/rc*.d/*audio > > > ls: Zugriff auf /etc/rc*.d/*audio nicht möglich: Datei oder > > > Verzeichnis nicht gefunden > > > $ sudo service pulseaudio stop > > > PulseAudio configured for per-user sessions ... (warning). > > > > > > Does the manual need updating? > > > > No, I think the manual is correct and update-rc.d is not behaving as > > documented. > > I wonder though, what is the disadvantage of leaving `/etc/init.d/name` > behind and `-f` has to be used to do so? As above, I think it's not so much about leaving the init script behind, as it is about preventing removing needed links inadvertently. > > Mind you, I've not seen this before. But I can also reproduce it: > > > > % ls /etc/init.d/cups > > /etc/init.d/cups > > % ls /etc/rc*.d/*cups > > /etc/rc1.d/K01cups /etc/rc2.d/S04cups /etc/rc3.d/S04cups > > /etc/rc4.d/S04cups /etc/rc5.d/S04cups > > % sudo update-rc.d cups remove > > update-rc.d: using dependency based boot sequencing > > % ls /etc/rc*.d/*cups > > zsh: no matches found: /etc/rc*.d/*cups > > % sudo update-rc.d cups defaults > > update-rc.d: using dependency based boot sequencing > > % ls /etc/rc*.d/*cups > > /etc/rc1.d/K01cups /etc/rc2.d/S04cups /etc/rc3.d/S04cups > > /etc/rc4.d/S04cups /etc/rc5.d/S04cups > > > > I'm fairly sure this didn't happen until recently. But there were only > > two changes to update-rc.d in 2012, and both were trivial changes which > > didn't affect this. This will need investigating in more detail. > > I tried it on a system with sysv-rc 2.88dsf-22.1 which has *not* been > converted to dependency based boot yet. There it behaved as described in > the manual. Thanks, that's useful to know. > > % sudo update-rc.d cups disable > > update-rc.d: using dependency based boot sequencing > > insserv: warning: current start runlevel(s) (empty) of script `cups' > > overwrites defaults (2 3 4 5). > > insserv: warning: current stop runlevel(s) (1 2 3 4 5) of script `cups' > > overwrites defaults (1). > > % ls /etc/rc*.d/*cups > > /etc/rc1.d/K01cups /etc/rc2.d/K01cups /etc/rc3.d/K01cups > > /etc/rc4.d/K01cups /etc/rc5.d/K01cups > > > > % sudo update-rc.d cups enable > > update-rc.d: using dependency based boot sequencing > > % ls /etc/rc*.d/*cups > > /etc/rc1.d/K01cups /etc/rc2.d/S04cups /etc/rc3.d/S04cups > > /etc/rc4.d/S04cups /etc/rc5.d/S04cups > > > > This converts the start links to stop links, and enable reverses this. > > Thank you for the explanation. Although skimming through the manual > pages, I did not find how these links are used. Links starting with »S« > are executed with the `start` argument and links starting with »K« with > the `stop` argument? Yes. This is classic System V init behaviour. When you enter a runlevel, you run all the S links with "start". When you leave a runlevel, you run all the "K" links with "stop"; actually the ways the scripts are run when you switch runlevels isn't quite that straightforward, but that's almost essentially what happens. Regards, Roger -- .''`. Roger Leigh : :' : Debian GNU/Linux http://people.debian.org/~rleigh/ `. `' schroot and sbuild http://alioth.debian.org/projects/buildd-tools `- GPG Public Key F33D 281D 470A B443 6756 147C 07B3 C8BC 4083 E800 _______________________________________________ Pkg-sysvinit-devel mailing list [email protected] http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/pkg-sysvinit-devel
