"Louise Cofield" <lcofield(at)box-works(dot)com> writes:
> The initdb seemed to go fine, the postmaster is running in the
> background, but createdb testdb results in this:
> FATAL: user "postgres" does not exist
> psql: FATAL: user "postgres" does not exist
> createdb: database creation failed
> whoami shows that I am clearly "postgres"
Sounds like you weren't postgres when you ran initdb. The only
initially existing PG user will have the name of the Unix user
who ran initdb. Check the ownership of the files under $PGDATA if
you aren't sure what you did.
regards, tom lane