Extract secret key material from OpenPGP secret keys
Extract just secret information out of OpenPGP secret keys
paperkey$ paperkey --secret-key-file ~/.gnupg/secring.gpg --output secret-key.txt$ gpg --export-secret-key keyid | paperkey --output paperkey.txt$ paperkey --pubring public-key.gpg --secret-key paperkey.txt --output restored-key.gpg