psql\(em run the interactive query front-end

.IR command.

.IP\e?

Get help information about the\e commands.

There are some environment variables which can be used in liu of

command line arguments; these are detailed below.

Additionally, the Postgres frontend library used by the psql application

looks for other optional environment variables to configure, for example,

the style of date/time representation and the local time zone. Refer

to libpq(3) for more details.

.PP

You may set any of the following environment variables to avoid

specifying command-line options:

.nf

hostname:PGHOST

port:PGPORT

tty:PGTTY

options:PGOPTION

realm:PGREALM

hostname:PGHOST

port:PGPORT

tty:PGTTY

options:PGOPTION

realm:PGREALM

.fi

.PP

If

.IR Kerberos

authentication is in use. If this environment variable is set, Postgres

will attempt authentication with servers for this realm and use

separate ticket files to avoid conflicts with local ticket files. See

separate ticket files to avoid conflicts with local ticket files.

See

.IR pgintro(1)

for additional information on

.IR Kerberos.

.PP

See

.IR pgintro(libpq)

for additional details.

.IR psql

returns 0 to the shell on successful completion of all queries,