Re: s6-log run script

From: Jan Olszak <jan.olszak_at_vestiacom.com>
Date: Fri, 4 Mar 2016 23:06:24 +0100

And this works perfectly.
I missed the -D option in backtick. :)

Yeah, /opt was just an example.

Thanks!

On Thu, Mar 3, 2016 at 2:09 AM, Laurent Bercot <ska-skaware_at_skarnet.org>
wrote:

> On 02/03/2016 23:52, Jan Olszak wrote:
>
>> #!/usr/bin/execlineb -P
>> if -nt
>> {
>> backtick -n S6_LOG_ARGS
>> {
>> redirfd -r 0 /opt/s6logargs.opts s6-cat
>> }
>> import -u S6_LOG_ARGS s6-log T $S6_LOG_ARGS
>> }
>> s6-log T s1000000 n10 /var/log/syslogd
>>
>
> That won't work for several reasons:
>
> * the if -nt will only return once s6-log returns. Since s6-log is a
> long-lived program, that won't happen unless there's an error in the
> s6-log invocation. Which is what is happening here.
>
> * execline is not like the shell: when you import S6_LOG_ARGS, it is
> evaluated as just one word - it's not split. So your s6-log invocation
> is given two arguments: T, and whatever is in S6_LOG_ARGS. Likely
> s6-log cannot interpret the contents of your opts file as one single
> argument, so it fails - and dies, and if returns, and you get the
> fallback.
>
> * Even if s6-log succeeded, you'd have the "if" process hanging around,
> and s6-log would be a child of if. That's not what you want: you always
> want the process to execute into your chosen avatar of s6-log in the end.
>
> Try something like this:
>
> -----
> backtick -n -D "s1000000 n10 /var/log/syslogd" S6_LOG_ARGS
> {
> redirfd -r 0 /opt/s6logargs.opts s6-cat
> }
> import -u -s S6_LOG_ARGS # notice the -s, to split the args
> s6-log T ${S6_LOG_ARGS}
> -----
>
> Also, traditionally, /opt is not a good place to store regular files,
> even global ones - you'd use /etc or a subdirectory of /etc for that.
> But that's your business. :)
>
> --
> Laurent
>
>
Received on Fri Mar 04 2016 - 22:06:24 UTC