I use OpenPGP card functionality of Yubikey NEO over NFC. I need to access other
OpenPlatform app on the Yubikey (non-pkcs#11) using pcsclite API.
After I run gnupg for the first time, and scdaemon is started, my other
application get an error "Sharing violation" (SCARD_E_SHARING_VIOLATION) when it
tries SCardConnect() (FWIW, I use mode SCARD_SHARE_SHARED).
Starting scdaemon with non-zero --card-timeout does not change the behaviour.
I believe that scdaemon ought to disconnect from the card after all its clients
are gone, maybe after a few seconds timeout.