Duncan Coutts wrote:
Hia Dominic,
I've looked into this a bit. I think I may now be less confused. :-)
On Wed, 2009-01-21 at 18:01 +0000, Dominic Steinitz wrote:
ls -ltr haskell_packages\doc\zlib-0.5.0.0 total 2 -r--r--r-- 1 user group 1327 Jan 21 11:37 LICENSE
Ah! Is that the only file that is read-only? That makes sense since it's an original source file from your read-only source control system. The System.Directory.copyFile function does not copy permissions (though it does try to) but it does (unhelpfully) copy the read-only attribute.
It may not be but a lot of packages only have a LICENSE file. I'll have a look tomorrow.
When I rebuild the package *without* having cleaned out haskell_packages then I get the access error. I think this is because cabal (copyFile) doesn't want to overwrite a read only file even though the directory permissions should allow it to do so.
Yes. The windows MoveFile function does not let us move a file over a file that has the read-only attribute.
It's an annoying interaction between the semantics of old DOS/FAT read-only attribute and new windows file permissions (ACLs).
The solution I think, is never to copy the read-only attribute when installing files. It's thoroughly unhelpful. I've got a patch to do this which I shall push to Cabal HEAD shortly. If you have a moment to help me test that it would be much appreciated.
Thanks very much. I'll try it out tomorrow.