scdaemon does not "see" card insertion

NIIBE Yutaka gniibe at
Wed Jul 5 02:23:06 CEST 2017


Matthias Apitz <guru at> wrote:
> The script 'scd-event' is only invoked on card removal (I do just en
> echo of the args):
> A card insert is only seen *after* some agent requires something, for
> example the SSH client needs access to the secret key on the card;

Right.  Scdaemon only watches the event of card removal and card reader

In the past, once, scdaemon implementation in 2.0 partially tried to
support watching insertion, too.  The name "scdaemon" would have implied
that, perhaps.  We couldn't go this road well, because a card reader is
shared resource and there are valid use cases for other cards.

Then, the development of scdaemon evolved as openpgp-card-helper for

This focus could stabilize the use case for GnuPG, and it resulted
less conflict for other use cases for card and card reader.

> On the UNIX system level the card insert triggers via devd(8) the start
> of /usr/local/sbin/pcscd and the card removal triggers a 'killall pcscd'.
> This is working fine, i.e. an inserted card is useable immediately, requesting 
> the PIN entry.

IIUC, system level service like devd can only handle the event of card
reader insertion, not card insertion.  I may be wrong here.

I think that it is good for your use case to use PC/SC daemon
and its related tool.

I found a tool named card_eventmgr in:

This may help.  (No, I don't have any experience with this tool.)

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