msql_connect() establishes a connection to a mSQL server.
In case a second call is made to msql_connect() with the same arguments, no new link will be established, but instead, the link identifier of the already opened link will be returned.
The link to the server will be closed as soon as the execution of the script ends, unless it's closed earlier by explicitly calling msql_close().
The hostname can also include a port number. e.g. hostname,port.
If not specified, the connection is established by the means of a Unix domain socket, being then more efficient then a localhost TCP socket connection.
注: While this function will accept a colon (:) as a host/port separator, a comma (,) is the preferred method.
The mSQL user name.
The mSQL password for username.