Using OS X 10.11.1 I'm hoping to run a setup where my SSH keys are adding using `ssh-add -c` and when the ssh agent is requested to use a particular key I receive a dialog asking for permissions (i.e. ssh-askpass).

I'm unable to get anything other then keys adding via `ssh-add -c` just not seeming to work at all. I can add the key and confirm the key is added via `ssh-add -l`, but when I go to connect to a host I eventually end up a password authentication.

I've installed XQuartz and have a DISPLAY env var set, as well as having tried setting the SSH\_ASKPASS env var with a path to an executable applicable for that. The executable doesn't seem to be being executed when I attempt the ssh connection though.

I've tried a few rounds of killing ssh-agent and re-adding keys with the env vars set with no luck.