Gentoo Archives: gentoo-portage-dev

From: Francesco Riosa <vivo75@×××××.com>
To: gentoo-portage-dev@l.g.o, "Michał Górny" <mgorny@g.o>
Subject: [gentoo-portage-dev] Re: [RFC] gpkg format proposal v2
Date: Tue, 13 Nov 2018 01:03:21
Message-Id: 804245a5-f73c-6ab6-6066-faafddafd16f@gmail.com
In Reply to: Re: [RFC] gpkg format proposal v2 (was: Re: [gentoo-portage-dev] [RFC] Improving Gentoo package format) by "Michał Górny"
1 Il 12/11/18 16:40, Michał Górny ha scritto:
2 > On Mon, 2018-11-12 at 01:21 +0100, Francesco Riosa wrote:
3 >> Il giorno dom 11 nov 2018 alle ore 22:17 Michał Górny <mgorny@g.o>
4 >> ha scritto:
5 >>
6 >>> On Sun, 2018-11-11 at 21:53 +0100, Michał Górny wrote:
7 >>> [...-]
8 >>> Of course, one option would be to use ZIP ;-).
9 > I wasn't serious there.
10 >
11 >> Zip archives have another big advantage; there is an index of files, so
12 >> listing the archive contents and extracting a single file is very fast and
13 >> does not depend from it's position in the archive.
14 >> The big disadvantage is that only "desktop" profile has unzip by default
15 >>
16 > The two main problems with ZIP is that:
17 >
18 > 1. As you noted, it's not present in core system packages.
19 >
20 > 2. It uses trailer format which means that you need to fetch the whole
21 > file before being able to process it.
22
23 Well, with some protocols (HTTP-1.1) and with a well behaving server
24 (content-length) this is doable, but limited indeed.
25 However the same is true for the tarball if the order of the contained
26 files is uncertain.
27
28 Since a tar file is sequential even to know contained files you need to
29 seek into the tarball and the number of seeks is dependant from the
30 number of files included in the tarball before the wanted one.
31
32
33 >
34 > There was also some patent hassle back in the day but I think it's no
35 > longer applicable today.
36 >