[petsc-dev] [Mike McQuaid] Re: [Homebrew/homebrew-core] PETSc: import from homebrew-science (#23598)

[Jed Brown]

Satish Balay <balay at mcs.anl.gov> writes:

> On Sun, 25 Feb 2018, Lawrence Mitchell wrote:
>
>> 
>> 
>> > On 25 Feb 2018, at 21:13, Jed Brown <jed at jedbrown.org> wrote:
>> > 
>> > 
>> > The try part of that commit (around os.remove) is necessary.  Also,
>> > "rmdir -p" provides a useful semantic in this context, but needs to be
>> > implemented manually in Python (or I don't know where that functionality
>> > is available in the standard library).
>> 
>> shutil.rmtree
>
> I think [in uninstall script] - we want to delete dirs only if the dir
> is empty.  [if not empty - it could contain files installed by a
> different package - as its common to install multiple packages in the
> same prefix]

Yeah, "rm -r" is much different from "rmdir -p".

> Also - thinking about it - its not clear if we can really do a proper
> uninstall - esp with --download-packages.
>
> Previously - 'make install' would also install the downloaded packages
> and we kept track of them for the uninstall script. But now - we let
> each package do its own 'make install' to the prefix location. But we
> don't have an 'uninstall' option for these externalpackages. [I don't
> know if any of them provide 'make uninstall' feature]

PETSc --download-* is a package manager, albeit very crufty (though it
gets the job done).  Basically all package managers function by
installing with a private DESTDIR, bundling up the result, then
unpacking into the target.