Description:
------------
Hi,
the mysql client libs allow using a user specified "my.cnf".
Such a configfile can already be set with mysqli_options and MYSQLI_READ_DEFAULT_FILE.
The configfile can contain a password for connections. Such a password is only read, if the password-parameter to the mysql_real_connect c-function is NULL.
Passing NULL as password to mysqli_real_connect gets converted to an empty string during zend_parse_method_parameters, so the configfile is not used for a password.
At http://www.phpschlampe.de/mysqli.patch is a tiny patch to allow NULL-values for the password. This patch is against 5.2.
After patching the following works:

<?php
$mysqli = mysqli_init();
mysqli_options($mysqli,MYSQLI_READ_DEFAULT_FILE,"/path/to/.my.cnf");
/*pass NULL as user/pass so that the values in the config-file are used*/
mysqli_real_connect($mysqli,"foo.bar.de",NULL,NULL); 
?>