On 22 January 2015 at 17:00, Neil Bothwick <n...@digimed.co.uk> wrote: > On Thu, 22 Jan 2015 16:43:32 +0800, Sam Bishop wrote: > >> I'll quote from the binpkg docs: >> >> Next to these, portage will check if the binary package is built >> >> using the same USE flags as expected on the client. If a package is >> >> built with a different USE flag combination, portage will either >> >> ignore the binary package (and use source-based build) or fail, >> >> depending on the options passed on to emerge >> >> So I'm fairly sure that implies they can coexist based on the >> directory structure. - >> http://wiki.gentoo.org/wiki/Binary_package_guide#The_PKGDIR_layout > > The package name is the same as the ebuild name but with a .tbz2 > extension, so how could portage cope with multiple variants with > different USE flags when there is only one name? There can be only one > package per ebuild and either the USE flags match exactly or they do not. > > You could get away with this with a limited set of profiles by having a > different $PKGDIR for each profile but to do it with random combinations > would require some sort of middleware to handle the requests and place > the specified packages where portage expects to find them. > > I think the check for USE flags is done using the IUSE and USE settings > in the package metadata, so even if a USE flag you don't use is added to > an ebuild, the package will no longer match. ISTR having to hack metadata > in /var/db in the past to avoid a rebuild of *Office. >
Thank you kindly Neil. You rephrasing what was right in front of my face in the docs finally lead to the lightbulb going off. Happens to all of us I suppose. The pkdir layout diagram isn't implying multiple versions of a single package, it is referring to multiple packages with a numeric shorthand. So this would require middleware, wrappers, or improvements to portage to cope with having overlapping packages like this. So interim functionality could be achieved with separate bin hosts directories for each of the baseline profiles with their default use flags. Once the infrastructure was stable then work could be undertaken to build some kind of wrapper, or enhancement to portage. > > -- > Neil Bothwick > > When companies ship Styrofoam, what do they pack it in?
