Re: Documentation issues with xorriso

[Glenn Washburn]

On Wed, 08 Sep 2021 19:35:28 +0200
"Thomas Schmitt" <scdbackup@gmx.net> wrote:

> Hi,
> 
> Glenn Washburn wrote:
> > Finally getting around to sending this as you requested.
> > https://unix.stackexchange.com/questions/666972/how-to-exclude-paths-from-being-extracted-when-extracting-an-iso-using-xorriso?noredirect=1#comment1258466_666972
> 
> Oh. That was you ?
> The main reason for asking for a mail to bug-xorriso is that
> stackexchange is at odds with my good old workstation's browser and
> with my mail address. So any substantial discussion has to happen
> somewhere else.

Yeah, its not a discussion site. I decided to use it though, because I
thought any answer might be useful to others in my situation.

> I did not come to a full decision yet about what to do about the
> exclusion feature at restore time.
> It is promised in the man page, therefore its lack is a bug. I should
> implement the feature and have already identified the place in the
> code where to do so.
> 
> But i am unsure yet how to interpret the -not_paths list. The man page
> says
>        disk_path is a path to an object in the local filesystem tree.
>        ...
>        -not_paths disk_path [***]
>            Add the given paths to the list of excluded absolute disk
> paths. ...
> 
> Is it plausible to the user to exclude the target paths rather than
> the source paths of ISO extraction ?

I was confused about this wording also, which is why I tried both. I
would say have it mirror the usage in iso creation (absolute paths
relative to the iso, right?)

> Relative paths get absolutified automatically. But that has its
> pitfalls with symbolic links:
> 
>   $ xorriso -not_paths x/y/z -- -status -not_paths
>   GNU xorriso 1.5.5 : RockRidge filesystem manipulator, libburnia
> project.
> 
>   -not_paths '/daten/dvdbuffer/x/y/z' --
>   $ pwd
>   /dvdbuffer
>   $ ls -ld /dvdbuffer
>   ... /dvdbuffer -> daten/dvdbuffer
> 
> But the file paths used by the restore functions begin by
>   /dvdbuffer/x/y/z
> 
> So i ponder whether i shall implement -not_paths as is described in
> the man page now, or whether i shall change the man page to say that
> with extraction from ISO the -not_paths are absolute in the ISO.
> 
> It never worked. So i feel some freedom of decision. :))
> 
> You have tried on stackexchange 2 times ISO path and once local disk
> path. May i take this as indication of the user's expectation ?

Well, I don't think I'm the average user by any means, maybe there
isn't one. But it does make sense to me that the paths should be
absolute to the iso, which has the added benefit that runs of xorriso
on the same iso with different extract dirs can use the same
-not_paths. Probably relative paths should be relative to any -cd
arguments already passed. How does that sit with your intuition?

Glenn