I have an OpenPGP smart card key (YubiKey NEO) as well as a local secret key installed in my GnuPG keyring.
I'd like to encrypt and sign a file with my card's key, not the key in my keyring. How can I specify what key I'd like to sign with?
If my filesystem secret key id is
DEADBEEF and my smartcard key is
DEADBEE5, how do I sign with that key?