[HEADS-UP] Moving /var/run and /var/lock to tmpfs in Rawhide

[Paul Howarth]

On 23/11/10 23:01, Lennart Poettering wrote:
> On Tue, 23.11.10 23:02, Till Maas (opensource at till.name) wrote:
>
>> The release notes section contains this:
>> | /var/run and /var/lock are now mounted from tmpfs, and hence emptied on
>> | reboot. Applications must ensure to recreate their own files/dirs on
>> | startup, and cannot rely that doing this at package installtion will
>> | suffice
>>
>> But this does not mention tmpfiles.d which you wrote can be used instead
>> of creating files or dirs on startup.
>
> Added a comment about this now.
>
>>>   c) YOU need to edit your .spec file and place a %ghost where
>>>   appropriate.
>>>
>>>   c) YOU need to test if you package still works, and if necessary file
>>>   AVC bugs, add an /etc/tmpfiles.d drop-in file to your program, or patch
>>>   it so that it is able to recreate these directories beneath /var/run on
>>>   its own.
>>
>> Imho there should be a packaging guideline to make it clear what needs
>> to be done in which cases. E.g. when to %ghost files and when not.
>
> I guess extending the guidelines with a line or two about this is a good idea.
>
>>> <snip>
>>> d /var/run/screens 1777 root root 10d
>>> d /var/run/uscreens 0755 root root 10d12h
>>> </snip>
>>>
>>> This encodes that two directories are created under the listed names, with
>>> automatic clean up after 10 days resp. 10 days and 12h.
>>
>> Removing /var/run/screens after 10 days sounds wrong. Even removing the
>> sockets inside /var/run/screens sounds wrong. Is this just a bad example
>> am I not understanding the age means.
>
> Sorry, it's not necessarily a great example.
>
> The aging stuff is mostly useful for things like /tmp itself.
>
>>> For more details consult the man page:
>>>
>>> http://0pointer.de/public/systemd-man/tmpfiles.d.html
>>
>> Here it says:
>> | If a file or directory is older than the current time minus the age
>> | field it is deleted.
>>
>> And when are the files and dirs created? Only when the system is
>> booted?
>
> Yes.
>
>> But then after installing an package that requires files to be created
>> by tmpfiles.d the system needs to be rebooted before it can be used. Or
>> will rpm call something that parses the appropriate tmpfiles.d file when
>> the package is installed / updated?
>
> Hmm, it has been suggested that we should make it possible to create
> these dirs in the .spec files by invoking the systemd-tmpfiles tool
> directly from the scriptlets. I guess we should add a nice interface for
> that. In the meantime it should be sufficient to simply place th right
> "mkdir -p -m ..." in the scriptlet. Of course it would be desirable if
> we have a single place where the dirs to create are encoded.

Why not create the directories in the initscript/systemd equivalent?

Paul.