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

[Smith, Barry F.]

> On Feb 25, 2018, at 9:46 PM, Jed Brown <jed at jedbrown.org> wrote:
> 
> 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.

   That's not how PETSc's works. It tells the each package the final prefix and each package installs into that location directly.