Apple added support for extended attributes to HFS+ in Mac OS X 10.4 Tiger:<p><a href="http:&#x2F;&#x2F;arstechnica.com&#x2F;apple&#x2F;2005&#x2F;04&#x2F;macosx-10-4&#x2F;7&#x2F;#extended-attributes" rel="nofollow">http:&#x2F;&#x2F;arstechnica.com&#x2F;apple&#x2F;2005&#x2F;04&#x2F;macosx-10-4&#x2F;7&#x2F;#extended...</a><p>Today, resource forks are actually exposed through the extended attributes interface:<p><a href="http:&#x2F;&#x2F;arstechnica.com&#x2F;apple&#x2F;2013&#x2F;10&#x2F;os-x-10-9&#x2F;9&#x2F;#tags-implementation" rel="nofollow">http:&#x2F;&#x2F;arstechnica.com&#x2F;apple&#x2F;2013&#x2F;10&#x2F;os-x-10-9&#x2F;9&#x2F;#tags-imple...</a><p>You can see the source code for all this in Apple&#x27;s Darwin open source repository.  Example: <a href="http:&#x2F;&#x2F;opensource.apple.com&#x2F;source&#x2F;xnu&#x2F;xnu-2782.40.9&#x2F;bsd&#x2F;hfs&#x2F;hfs_xattr.c" rel="nofollow">http:&#x2F;&#x2F;opensource.apple.com&#x2F;source&#x2F;xnu&#x2F;xnu-2782.40.9&#x2F;bsd&#x2F;hfs...</a><p>Please read this, written by the creator of resource forks, to learn why they exist:<p><a href="http:&#x2F;&#x2F;www.folklore.org&#x2F;StoryView.py?story=The_Grand_Unified_Model.txt" rel="nofollow">http:&#x2F;&#x2F;www.folklore.org&#x2F;StoryView.py?story=The_Grand_Unified...</a>