Cannot initdb on fresh install

Greetings

I am attempting a fresh install of postgresql9.5 on FreeBSD
I am at the point of initialising the database server. When I issue the
initdb command (see below) I am requested to enter a password. Which
password am I meant to insert here?
When I cat /etc/passwd I notice there is a user pgsql ( a pseudo user)
which I never created so I dont know what the password is for pgsql.
I have tried using the root password, my user's password, and a user I
created (postgres) but all to no avail.
Can anyone help me along?
Regards
Dimitri


$ /usr/local/etc/rc.d/postgresql initdb
Password:
su: Sorry