OS X, tar and Resource Forks

21 March 2007

In preparing releases of Jabber::Bot, I had my first experience using tar in OS X to produce a tarball; I had previously only been a consumer of tarballs in OS X.

Using OS X on the command line means dealing with resource forks. Especially when doing things like copying or archiving files for public distribution. Most heavy OS X users are familiar with .DS_Store files. They are a nuisance, but generally can be dealt with without much fuss. Resource forks, on the other hand, can sometimes be tricky.

Resource forks serve no purpose to anyone but you or another OS X user, who likely doesn’t really care anyway. In order to create a public tarball, it’s a good idea to exclude resource forks since they are unnecessary. But, tar on OS X (Tiger) likely won’t exclude them, even if you specify an exclude pattern like --exclude='._*'.

After a bit of tinkering, I found a solution:

$ export COPY_EXTENDED_ATTRIBUTES_DISABLE=true

Then run tar and resource forks will be excluded.