[launchd-dev] Is there anything that can prevent launchd from working

[Scott Haneda]

On Jun 1, 2009, at 12:32 PM, Damien Sorresso wrote:

> On Jun 1, 2009, at 12:00 PM, Scott Haneda wrote:
>> In a case where launchd works just fine all the time, for example:
>>
>>   [snip...]	
>>    echo "Sleeping...90 Seconds     `date`" >> $log_path
>>    /bin/sleep 90;
>>
>>    # Do the work
>>    echo "About to run ntpdate -u" >> $log_path
>>    /usr/sbin/ntpdate -u
>>    echo "Finished running ntpdate -u" >> $log_path
>>
>> log... (Full output, non shortened)
>>    ----- BEGIN -----
>>    Started to set time and date
>>    Mon Jun 1 11:18:35 PDT 2009
>>    Sleeping...30 Seconds     Mon Jun  1 11:18:36 PDT 2009
>>    Sleeping...30 Seconds     Mon Jun  1 11:19:06 PDT 2009
>>    Sleeping...15 Seconds     Mon Jun  1 11:19:36 PDT 2009
>>    About to run ntpdate -u
>>    Finished running ntpdate -u
>>    Finished setting time and date
>>    ----- END -----
>
> You should use the StandardOutPath key (pointing to /Users/me/ 
> Library/Logs/ntpdate.lo) in your launchd job, that way your script  
> doesn't have to worry about echo(1)ing to a log file. Its stdout  
> will just be redirected to the log file. This results in less  
> complexity for your script.

Nice, thanks.  What gets passed into StandardOutPath?  I assume  
anything the script outputs via a plain echo, will be intercepted to  
the log?  This is really nice, as I can then debug scripts as usual,  
and not have to run a tail -f on some log somewhere.

>> Syslog tells me it works:
>> Jun  1 10:57:41 host com.host.ntpdate[19696]:  1 Jun 10:57:41  
>> ntpdate[19776]: adjust time server 17.151.16.21 offset -0.070842 sec
>>
>> It works all the time, sans one case, which is when I need it  
>> most.  I hope there are people here who know a but about the kernel  
>> of OS X.  When the machine panics, which I am still working on  
>> determining why, I suspect ram, though on the 3rd batch.  I have  
>> 100% ruled out a bad pram battery.
>>
>> After a panic, the "automatically restart after power failure"  
>> feature does not work.  It does work any other time, only after  
>> panics does not it.  I have to physically reboot.  This also adds  
>> more credence to the battery being fine.
>>
>> When the machine comes up, there is a message on screen about the  
>> date and time being at 1969.  Doing a google search for "panic  
>> 1969" and you see there are a good deal of others with panic logs  
>> at 1969.  I conclude, panics mess with the date and time for some  
>> reason, or nuke nvram, not sure.
>>
>> No big deal really, though this is an email server, and if I  
>> forget, or do not have access, the date and time will continue to  
>> be wrong, and all emails will be wrongly dated.
>>
>> My plist is set to run at load, and also to run every 60 minutes,  
>> which I see it does do.  I can find a syslog line that shows it ran  
>> at load, and ones that show it runs every hour as well.
>>
>> launchd totally fails to run this item after a kernel panic and the  
>> date is set into the 1969 range.  I have the sys log for where the  
>> dates are all Dec 31, which is just after the panic, and after I  
>> called in a reboot, which then foiled my script from setting the  
>> date correctly.
>>
>> I see named started, which uses launchd, so I know it is working.   
>> I see a lot of other things start.  But then I see this:
>>
>> Dec 31 16:00:54 host-domain-com com.apple.launchd[1]  
>> (com.domain.ntpdate[50]): Exited with exit code: 1
>
> You're drawing bad conclusions. launchd did, in fact, start the job.  
> It has a PID and exit status and everything. The job just exited  
> unsuccessfully. Not really launchd's fault. Don't interpret "The job  
> failed" as "launchd did not start the job". All we do is start the  
> job and get out of the way.

Ok, understood.  The trouble is, ntpdate is failing then, and I have  
no way to get the date set to 1969.  Any attempts to do so via GUI,  
drop it back to current date.  I can shove it to some other date, but  
ntpdate does not error when run.

How can I mimic from an interactive shell exactly what launchd is  
doing, so I know I am on the same page?  Any idea how to get the  
system clock into 1969?  I really do not want to pull a pram battery  
in this laptop :)

Thanks so much, I will follow up and see if I can find a ntpdate list.
-- 
Scott * If you contact me off list replace talklists@ with scott@ *