(PHP 4, PHP 5)
pg_host — Returns the host name associated with the connection
$connection
  ] )
   pg_host() returns the host name of the given
   PostgreSQL connection resource is
   connected to.
  
connection
     
       PostgreSQL database connection resource.  When 
       connection is not present, the default connection 
       is used. The default connection is the last connection made by 
       pg_connect() or pg_pconnect().
      
   A string containing the name of the host the 
   connection is to, or FALSE on error.
  
Example #1 pg_host() example
<?php
$pgsql_conn = pg_connect("dbname=mark host=localhost");
if ($pgsql_conn) {
   print "Successfully connected to: " . pg_host($pgsql_conn) . "<br/>\n";
} else {
   print pg_last_error($pgsql_conn);
   exit;
}
?>