[PATCH] 2/2: Associate file locations to newly introduced path variables

[Christian Perrier]

Quoting Andrew Bartlett (abartlet at samba.org):

> I think the only separation you are likely to get Jerry to agree on is
> between those databases marked as 'clear if first' (lifetime of the
> process), and those which expect to be persistent (longer than that).
> 
> This is a distinction already used by CTDB to determine how a database
> needs to be handled on clustered nodes. 

To make things clear, we can go back to the definition of /var/cache
in the FHS:

----------------------------------------------------------------------
/var/cache : Application cache data

Purpose

/var/cache is intended for cached data from applications. Such data is
locally generated as a result of time-consuming I/O or
calculation. The application must be able to regenerate or restore the
data. Unlike /var/spool, the cached files can be deleted without data
loss. The data must remain valid between invocations of the
application and rebooting the system.

Files located under /var/cache may be expired in an application
specific manner, by the system administrator, or both. The application
must always be able to recover from manual deletion of these files
(generally because of a disk space shortage). No other requirements
are made on the data format of the cache directories.

Tip  Rationale
 
  The existence of a separate directory for cached data allows system
  administrators to set different disk and backup policies from other
  directories in /var.
----------------------------------------------------------------------


As one sees, the "clear if first" files fall in that category.....but
not only these ones. For instance, the *_cache.tdb files mentioned in
Jerry's argument seem to be well represented by "The data must remain
valid between invocations of the application and rebooting the system."

As a way to advance in this discussion, we could maybe check files
mentioned in our patch 2/2 one by one and see if we agree or not about
the location they should be WRT the FHS.