KMail and smartcard - what is a "stub" secret key ?

[gpg.20.subu at spamgourmet.com]

Hi


I'm new here

Sorry to butt in 

>
>For gpg it makes no difference whether the key is on the disk or on
>the card.  This is because we create a "stub"- secret key for every
>card key.  gpg -K will show you the serial number of the cards
>associated with that secret key.
>


what is a "stub" secret key  ?

I thought that If I keep my keyring on a USB drive, there would be *no
trace of it* on the Hard Disk

Somehow your answer seems to imply that the Hard Disk has some info
about keys on other drives 


TIA

Subu

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>



Werner Koch - wk at gnupg.org wrote:

>On Tue, 24 May 2005 06:41:24 +0200, Chris  said:
>
>>How can I use the smartcard in KMail? I cannot choose its keys in the Identity 
>>management.
>
>
>Does "gpg -K" list your key?  This is what Kmail displays.
>
>You are using a decent Kmail (with all the crypto tabs in the
>configuration dialog and the requirement for gpg-agent)?
>
>>Using a key from the harddrive does work without problems.
>
>
>For gpg it makes no difference whether the key is on the disk or on
>the card.  This is because we create a "stub"- secret key for every
>card key.  gpg -K will show you the serial number of the cards
>associated with that secret key.
>
>If you generated the card key on another machine, please run "gpg
>--card-status" once on the new machine to create such a stub key.
>
>
>Shalom-Salam,
>
>   Werner
>
>