Hi, On 2022-01-23 18:31:44 -0500, Tom Lane wrote: > Andres Freund <and...@anarazel.de> writes: > > On 2022-01-23 18:11:41 -0500, Tom Lane wrote: > >> Anyway, trying to figure out whether we're on a Debian package with this > >> mistake doesn't seem any cleaner than what I proposed. (In particular, > >> blindly changing to a different scheme without a check to see what's really > >> in the filesystem seems doomed to failure.) > > > If we make it depend on _get_default_scheme() == 'posix_local' that > > shouldn't > > be a risk, because that's the debian addition... > > Yeah, but we don't know whether there are any versions of the Debian > packaging in which they fixed the file layout, so that 'posix_local' > actually does describe the layout.
I think posix_local try to achieve something different than what you assume it does. It's intended to return the location to which "locally" intalled python extension install their files (including headers) - after having the problem that such local python package installations overwrite (and thus broke) files installed via the system mechanism. So posix_local works "by design" if it returns paths in /usr/local that do not contain a python installation. If it did, it wouldn't achieve the goal. It's definitely crappily documented. And probably not a great approach as a whole. But... Greetings, Andres Freund
