On Friday 12 February 2010 08:12 PM, Marko Vojinovic wrote: > On Saturday 13 February 2010 00:09:38 Suvayu Ali wrote: >> On Friday 12 February 2010 06:06 AM, Marko Vojinovic wrote: >>> Now, hard links are not allowed for directories since they would allow >>> for creation of loops (a directory containing itself), which is a Bad >>> Idea, since it breaks recursion. The filesystem needs to be a *tree* if >>> recursion is to function, so loops are forbidden (how would you delete a >>> directory which contains itself?). >> >> I don't quite follow you here, don't you mean hardlinking directories >> have the risk of introducing recursion? > > No, I am saying that hard linking directories allows creation of loop > structures. These structures break any recursive algorithm that tries to go > "downwards" in some directory structure. > > Deleting directories is a textbook example. In order to delete a directory, > you first have to delete all files and subdirectories that it contains, and once > it is empty, delete the directory itself. So deletion goes on via a recursive > algorithm: > > 1) check whether there are files or dirs in target dir > 2) delete any files present > 3) execute yourself (from step 1) for every subdir as target dir > 4) target dir is now empty, unlink it > 5) done I think I had misunderstood what you said the first time. I wasn't thinking in terms of the algorithm traversing through the directories. :-p Its all clear now. > Best, :-) > Marko > Thanks a lot everyone. This has been incredibly educational. :) -- Suvayu Open source is the future. It sets us free. -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
