( [string hostname] )
msql_pconnect() acts very much like
msql_connect() with two major differences.
First, when connecting, the function would first try to find a
(persistent) link that's already open with the same host.
If one is found, an identifier for it will be returned instead of opening
a new connection.
Second, the connection to the SQL server will not be closed when the
execution of the script ends. Instead, the link will remain open for
future use (msql_close() will not close links
established by this function).