(PHP 4 >= 4.2.0, PHP 5)
pg_connection_status — Get connection status
$connection
   )
   pg_connection_status() returns the status of
   the specified connection.
  
connectionPostgreSQL database connection resource.
    PGSQL_CONNECTION_OK or 
    PGSQL_CONNECTION_BAD.
   
Example #1 pg_connection_status() example
<?php
  $dbconn = pg_connect("dbname=publisher") or die("Could not connect");
  $stat = pg_connection_status($dbconn);
  if ($stat === PGSQL_CONNECTION_OK) {
      echo 'Connection status ok';
  } else {
      echo 'Connection status bad';
  }    
?>