Establishes a persistent connection to a FrontBase server.
To set the server port number, use fbsql_select_db().
fbsql_pconnect() acts very much like fbsql_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, username and password. 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.
This type of links is therefore called 'persistent'.
The server host name. Defaults to localhost.
The user name for the connection. Defaults to _SYSTEM.
The password for the connection. Defaults to the empty string.
Returns a positive FrontBase persistent link identifier on success, or FALSE on error.