• Linux.com :: Protecting directory trees with gpgdir
  gpgdir uses GNU Privacy Guard (GnuPG) to encrypt and decrypt files or a directory tree. You could accomplish the same objective by tarring the filesystem up and then encrypting the tar.gz file with GnuPG, but then you would still have to shred or wipe every file in the original directory tree. With gpgdir the whole tree is encrypted in one command.
  in Privacy > Linux encryption tutorials with command decrypt encrypt encrypted encrypting file filesystem gnu gnupg gpgdir privacy shred wipe

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