git commit signing: Asked for smartcard as it's plugged in

[Gabriel Augendre]

Hello,

This question has originally been posted to GPGTools support [1], who
redirected me there.

I'm trying to use GPGTools for git commit signing, using a MacBook Air
(macOS 10.13.3) and gpg version 2.2.3.

I used this tutorial [2] (I guess, it was a while ago) to generate a
key pair and add subkeys to my yubikey.

Whenever I need to sign a git commit, I need to plug my Yubikey in and
type the pin code. That works perfectly just after logging into my
session, but if the computer goes to sleep (that's my guess, not sure
about that) and I wake it up and try to sign another commit, GPGTools
pinentry keeps asking to plug the yubikey in even though it's already
there.

As a workaround, I'm forced to go to the terminal, killall gpg-agent
and then retry the operation, then it works. Do you have any idea why
that happens ?

Best regards,
Gabriel

[1] https://gpgtools.tenderapp.com/discussions/problems/69206-asked-for-smartcard-as-its-plugged-in
[2] https://www.yubico.com/support/knowledge-base/categories/articles/use-yubikey-openpgp/