Re: [9fans] Content of your /rc/bin/service or /dis/svc ?

[Edouard Klein <edou@rdklein.fr>]

sirjofri <sirjofri+ml-9fans@sirjofri.de> writes:

> Hi,
>
> 05.03.2024 22:38:59 Edouard Klein <edou@rdklein.fr>:
>
>> Hi,
>>
>> Thank you for your answer.
>>
>>
>> sirjofri <sirjofri+ml-9fans@sirjofri.de> writes:
>>
>>> Hello,
>>>
>>> I don't use /rc/bin/service anymore, but I use /cfg/machinename/service instead. My contents are copies of what's in /rc/bin/service or my own scripts:
>>
>> I assume that you then bind-mount /cfg/machinename/service to that
>> machine's /rc/bin/service ?
>
> Nope, because bind would only change my own namespace (or I have to bind it becore aux/listen starts).
>
> In fact, it's much easier. I don't know if it's a 9front feature or if it's also
> in plan 9, but if there is a /cfg/$sysname/service directory it will use that
> instead of /rc/bin/service (see the cpurc file,
> https://git.9front.org/plan9front/plan9front/36478171be59721dcc5252043fe2955cb37fc9b3/rc/bin/cpurc/f.html
> ).
>
Thanks, I had missed it because there is no /cfg in the source. Do you
happen to know how the /cfg dir is first populated during install ? Is
it all hand-written by the user ?

>
> If you think about how plan 9 should run on a network, imagine a single fs with
> many cpu servers all using the same fs. All the configuration is on the fs, and
> the service directories are in the /cfg/machinename/service. The cpu servers
> will run their individual configuration automatically using that mechanism. It
> just makes sense.
>

Indeed it does.

>>>
>>> tcp80 - web server
>>> tcp443 - web server but wrapped in tls
>>> ...
>>>
>>> I have some cifd running, some irc server that translates to grid chat, my mail
>>> server (smtp and imap4), and fingerd, the files follow the usual scheme tcpXXX.
>>> I probably missed one service or the other, but aux/listen is simple enough to
>>> set up custom servers with arbitrary functionality.
>>>
>>
>> Would you mind sharing your fingerd and irc server ? For finger my plan
>> is to turn this one:
>> https://github.com/michael-lazar/finger2020/blob/master/finger2020 into
>> a multi-user version, but if there already is one I won't bother.
>
> Sure, here it is:
>
> https://shithub.us/sirjofri/fingerd/HEAD/info.html
>
> Note that I got some notice of potential .. path issues and I'm not sure if I
> fixed that, but just in case, you might want to fix that (and maybe send me a
> patch). Fix could be as easy as a newns or what it is in C.
>

I'll try to compile it on Linux and will let you know :)

>>> If you have exact questions about aux/listen functionality or you don't understand something, just ask :)
>>>
>>
>> - I noticed some tcpXXX files use exec for their last line, and some
>> don't. Is there a reason ? My understanding is that exec saves one call
>> to fork per connection, and thus it would be best if it was always used.
>
> There might be some difference, maybe with log redirectors or something, but I
> don't know about that. I guess someone else can tell us more about this (and the
> following topic, which is very similar)
>
>> - I noticed Inferno makes great use of servers that speak 9P on their
>>   stdstream, with its
>>   mount {some-program} /mnt/toto
>>   These programs are trivial to expose thanks to listen:
>>    listen -v 'tcp!*!toto' {some-program&}
>>   On Plan9, I ran into rc's cmd <[0=1] | echo 0 > /srv/name, then mount
>>   /srv/name /n/toto.
>>   - Is there a inferno-like shorthand for Plan 9 ?
>>   - Why the "echo 0" ? (I'm not familiar with rc).
>>
>>> Btw it's quite common to "deactivate" services by renaming the files to have a
>>> leading "!". In general, everything that follows the naming scheme
>>> <protocol><port> and is executable will work.
>>>
>> why not just chmod -x them ? In a multiuser system, users may not have
>> the right to rename them.
>
> I think that _would_ work, but I think it's about readability in this case. I
> can just lc in that directory and immediately see what's relevant and what not.
> With executable flag I have to run ls -l to see what's executable, and it's also
> harder to parse it (sorting and filtering). A simple ! is easier to read, and
> also probably more stable in case of copying files via different filesystem
> types (like, copying the file to fat32 and back, or even having a filesystem
> without executable flags, which often results in all files bein executable).
>

Thanks for all this info !

> 
> sirjofri

------------------------------------------
9fans: 9fans
Permalink: https://9fans.topicbox.com/groups/9fans/Tf73851503467346f-Mf9cb49da52d37653059fdaa2
Delivery options: https://9fans.topicbox.com/groups/9fans/subscription