Pbins

Format Overview

Paludis uses its own format for binary packages built from ebuild or exhereses. This format is known as 'pbin'. It is not in any way compatible with Portage's tbz2 packages, which we consider to be too broken to be worth handling.

A pbin comes in two parts. First, there is the pbin file itself, which is a small file containing metadata information. Second, there is the tarball containing the content of the package, along with environment information to allow pre- and post-install functions to be run as if the package were being installed from source.

pbin files should be considered to be more or less like an ebuild or exheres -- in particular, they are kept in a repository, which can be shared and synced using the normal mechanisms. There is nothing special about repositories that contain binary packages, and it is in principle possible to mix binary and source packages within an individual repository (although doing so is a bad idea).

Similarly, the content tarball is treated just like source tarballs for ebuilds and exhereses. It is stored in a distfiles directory rather than in the repository, and can be fetched from a remote location (which might be mirrored) when it is required.

Using a binary repository is just like using a normal ebuild or exheres repository, and does not require any special configuration. The importance setting may be of interest here, however -- using a high importance for a binary repository will result in packages in that repository being preferred, whilst using a low importance will result in binaries only being used when necessary or explicitly requested.

Notes on libarchive

We use libarchive to create binary packages, and require version 3.0.4 or greater.

Creating Binary Repositories

If one wishes to create binary packages, either for local use or for distribution, then some additional configuration is required. In general:

• Create a new, empty repository, exactly as you would for an overlay containing ebuilds or a supplementary repository containing exhereses. Give it a name, like fred-bin. Configure Paludis to use this repository as normal.
• In addition, specify keys like the following in the configuration file (see the e repository documentation for full details):

  binary_destination = true
  binary_distdir = ${distdir}
  binary_keywords_filter = amd64 ~amd64

• If your binary repository is intended for non-local use, you may wish to use a different directory for binary_distdir, to make distributing generated tarballs simpler. In this case, you should also specify binary_uri_prefix = http://yourserver/wherever (or mirror://yourname/ and then also set up a thirdpartymirrors (Gentoo) or mirrors.conf (Exherbo) as part of your repository.

Creating Binary Packages

Creating binary packages is done for two reasons.

• Creating binary packages may be a direct goal, either for local use or for publishing. In this case, cave resolve --make binaries can be used. The --make-dependencies option will likely also be of interest.
• Creating binary packages may be a desired side effect, either to avoid building a package twice to install to slash and a chroot, or just to have something around for possible use when installing a package normally. In this case, cave resolve --via-binary is a more appropriate solution.

Creating binaries using the old paludis client is not recommended, since it is not aware of the subtleties of dependencies with binary packages.