>Presumably, you are working with a distro-modified version of Postgres,
>because the stock sources don't use /var/run/postgresql as a socket
>directory. You will likely find that your version of libpq.so also
>expects /var/run/postgresql as the socket directory, so you won't be
>able to make non-TCP connections without explicitly specifying /tmp
>(or wherever you choose to put the socket) as the host location.
Using the following fromsudo yum install postgresql-server postgresql-contrib
postgresql-server-9.2.15-1.el7_2.x86_64
postgresql-contrib-9.2.15-1.el7_2.x86_64
postgresql-9.2.15-1.el7_2.x86_64
postgresql-libs-9.2.15-1.el7_2.x86_64