How can I create a zip archive for Windows and Linux users?

In Finder, when I create an archive ("Compress items..."), the resulting zip archive has .DS_Store files in folders and files have resource forks. How can I create a zip archive suitable for cross platform sharing from Mac OS X?


Solution 1:

  • zip -r -x .DS_Store directory.zip directory
    • zip removes extended attributes and ACLs by default
  • find directory -name .DS_Store -delete; ditto -ck --norsrc directory directory.zip
    • --norsrc implies --noextattr and --noacl; --noextattr would require --norsrc
    • -c is compress, -k uses PKZip (zip) instead of CPIO
  • COPYFILE_DISABLE= tar --exclude .DS_Store -czf directory.tgz directory
    • Setting COPYFILE_DISABLE tells tar to remove extended attributes and ACLs instead of creating ._ files

The files that start with ._ are AppleDouble files (not resource forks), and they are used to store extended attributes and ACLs.

Extended attributes are used to store the quarantine status of files, the source URLs of files downloaded from the Internet, information about aliases (aliases stop working if extended attributes are removed), Spotlight comments, the encoding of files saved with TextEdit, and so on.

You can list extended attributes and ACLs with ls -l@e. You can remove extended attributes and ACLs recursively with xattr -cr .; chmod -NR .

Solution 2:

You can use the ditto command.

ditto -ck --norsrc sourcedir destination.zip

-c create an archive
-k create a PKZip archive instead of the default, which is CPIO
--norsrc do not preserve the resource forks

I think this will still include .DS_Store files, though.