main (sample/test2.rb)

    # File sample/test2.rb, line 16
    def main
      pghost = nil
      pgport = nil
      pgoptions = nil
      pgtty = nil
      dbname = ENV['USER']
      begin
        conn = PGconn.connect(pghost,pgport,pgoptions,pgtty,dbname)
      rescue PGError
        printf(STDERR, "Connection to database '%s' failed.\n",dbname)
        exit(2)
      end
      begin
        res = conn.exec("LISTEN TBL2")
      rescue PGError
        printf(STDERR, "LISTEN command failed\n")
        exit(2)
      end
      res.clear
      while 1
        notify = conn.get_notify
        if (notify)
          printf(STDERR,"ASYNC NOTIFY '%s' from backend pid '%d' received\n",notify[0],notify[1])
          break
        end
      end
    end