[systemd-devel] [PATCH V4] service: Support environment variable substition for PIDFile=

[Harald Hoyer]

Am 18.04.2013 02:40, schrieb Lennart Poettering:
> On Wed, 10.04.13 16:53, harald at redhat.com (harald at redhat.com) wrote:
> 
>> From: Harald Hoyer <harald at redhat.com>
>>
>> This patch adds environment variable substition for PIDFile=. To read
>> the environment files only once, ExecContext holds a copy of the
>> environment gathered.
>>
>> RFE: https://bugzilla.redhat.com/show_bug.cgi?id=840260
> 
> I am really not convinced about this one. The final environment is only
> put together right before we execute a binary, and resolving this much
> earlier sounds like the wrong thing to do, because it would necessarily
> not be in sync with the environment we pass to the binary.
> 
> Also, we currently do not resolve environment variables in any directive
> except ExecXYZ=. If we begin doing this here, then people want it
> everywhere, and things become really messy...
> 
> This makes it particularly hard for people to write sane external parsers
> for this, since suddenly to understand unit files you actually need to
> resolve env vars, it is no longer sufficient to resolve env vars only
> when executing things, i.e. to leave that to systemd...
> 
> Then, the whole PID file story looks like a mess to me anyway, modern
> daemons should not use PID files anyway... Even more, making them
> configurable sounds really wrong. If this is about allowing
> instantiation, then people can use %i in the PID file name, and be done
> with it, but otherwise this sounds like a completely ridiculous
> configuration option in sysconfig, like the first one to get rid
> of... So the usecase already sounds really wrong to me, to start with.
> 
> This really sounds like a bug to me we should close WONTFIX with a nice
> explanation. I know Tom won't like that, but well, sometimes we have to
> say No to wishes.
> 
> I know I though different about this in January (and commented so in the
> bug), but in retrospect I must disagree with myself on this...
> 
> Sorry,
> 
> Lennart
> 

fair enough, care to close the bug then?