Re: [Gnu-arch-users] Re: arch with 'special files'

[Josh England]

address@hidden wrote:
>>Hm, it's not that easy. There will have to be a set of data types
>>(content, type, permissions, ...) that will be recorded for each file,
>>and a set of procedures to diff and patch them. This set should be
>>extensible and might be different on each platform. However, all the
>>standard mapping would have to be built in.

Again, the set of data type for which arch should do any implicit
'diffing' should be *very limited*.  (Plain text) content, file type,
permissions, (optinal) ownership, and (optional) CR/LF come to mind.
Everything else can be handled with (plain text) user-level metadata.
Arch would store it, but the user would have to deal with it.

>>Note, that for security reasons arch must not run archive-provided
>>scripts, so the diff algorithm specification has to be flexible enough
>>to be actually useful.
> 
> 
> *This* could turn out to be a real killer. I think it'd be difficult
> to get things right in the first place. As your attribute set evolves
> (along the archive's life) your attribute-related algorithms might
> want to evolve too.
> 
> How does one solve that?

Effectively, punt.  User-level metadata is the user's problem.  They
would have to handle it in specialized post-update wrapper scripts.

-JE