gistfile1.txt

$ psql -d bench
Welcome to psql 8.3.6, the PostgreSQL interactive terminal.

Type:  \copyright for distribution terms
       \h for help with SQL commands
       \? for help with psql commands
       \g or terminate with semicolon to execute query
       \q to quit

bench=# select pg_backend_pid();
 pg_backend_pid
----------------
          16588
(1 row)

bench=#