Is use_7z worth it? (was: Re: [57743] trunk/dports/graphics/ImageMagick/Portfile)

[Anders F Björklund]

Ryan Schmidt wrote:

>> You are mixing archive formats with compression formats...
>
> It's hard not to, since they're so related. :)

Indeed! It's also a problem for things like MacPorts that calculates
checksums/digests on the *compressed* tarball. This means that changing
compression changes the digest, which isn't really "perfect" either.

There are other ways of calculating the digest, so that it would be
the same no matter which compression is being used... Like doing it
on the uncompressed .tar, or making a "manifest" of the included files.

>> I don't have a major problem with it either (if I appeared to),
>> just like you could use the .zip file instead of the .tar.gz.
>> Just saying that generally it would be preferred to use .tar.xz,
>> so you probably want to be adding that "use_xz" flag to MacPorts.
>
> Yes, I think we should add it too, but I am uncomfortable doing so  
> until a stable version of xz exists. It does not seem right for a  
> core MacPorts functionality to depend on an unstable version of a  
> software package.

Presumably the format itself is stable, but the software isn't yet.
It's still possible to use .lzma meanwhile, since that's released.

And I don't think that the actual implementation of "use_xz" would
change much though, between the current XZ beta and the XZ release ?

>> For instance, 7z doesn't store UNIX owner/group permissions...
>
> I read that claim on the Wikipedia page, but am unable to  
> substantiate it. The 7z archive of ImageMagick does have the  
> execute bit of the configure script set, for example.

Maybe it's gotten better since, the p7zip (portable version) used
to be a bit behind. I don't think it had the LZMA2 before either...

But it still has "weird" command-line options etc (just like unzip),
whereas xz/lzma (or gzip) has the usual options and tar integration ?

--anders