Re: replicating package compression used by dpkg-deb
Followup to the other lists too...
On Thu, Sep 28, 2006 at 12:15:21PM +0100, Mark Brown wrote:
> On Thu, Sep 28, 2006 at 03:45:16AM -0700, Ian Bruce wrote:
> > It appears that dpkg-deb does not exec gzip, and it's not dynamically
> > linked with anything except glibc. I suppose that it's statically linked
> > against zlib1g or something like it. So the question is, how can the
> > exact compression algorithm used by dpkg-deb be made available for
> > another piece of software? Is it something that's well-specified, or is
> > it liable to change at any moment?
> dpkg is statically linked against zlib (you really don't want to break
> the ability to unpack packages if you can avoid it). I presume dpkg-deb
> is too though I haven't checked. The precise output of zlib can vary
> between versions and depending on the options used when running it.
> > Of course the whole problem would be radically simplified if the
> > "--rsyncable" option were used when the packages were being built. Does
> > anyone know what the rationale for not doing that is?
> It's not implemented by zlib. There is an open bug report asking for
> it with a link to a patch but I wasn't happy with the patch since it
> is enabled using an environment variable and wanted to rework it to have
> an API before forwarding upstream. I've not yet had sufficient
> enthusiasm to do that; current progress suggests that you shouldn't hold
> your breath on that one.
> "You grabbed my hand and we fell into it, like a daydream - or a fever."
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"You grabbed my hand and we fell into it, like a daydream - or a fever."