Is there a way to view active connections?

I want to do a server restart, so I issued the command
pg-ctl -w restart -D /usr/local/pgsql/data

However, the shut down fails:
pg_ctl: server does not shut down.

Unfortunately, when I try to see who is connected with psql, I get
FATAL: the database system is shutting down.

Is there any other way to see who is still connected?

Thanks --Fred

ABAG is moving.
Effective Monday May 23, 2016 our mailing address and location will be:
Association of Bay Area Governments
375 Beale Street, Suite 700
San Francisco, CA 94105
(415) 820-7900

My email address will remain the same.
My phone number will be (415) 820-79XX (last two digits remain the same).
We look forward to seeing you at our new location along with our regional partners, the Metropolitan Transportation Commission and the Bay Area Air Quality Management District.
In the meantime, it's business as usual at our current location in Oakland.