This script is a great idea. It helped me solve this 'Cannot connect to database' problem.

The problem turned out to be that the location of the mysql.sock as returned by this script did not match the location as listed in either php.ini or my.cnf.

My situation was:

this script and info.php
-------------------------
MYSQL_SOCKET /var/lib/mysql/mysql.sock

php.ini
-------
mysql.default_socket /var/run/mysql/mysql.sock

my.conf
-------
socket /var/run/mysql/mysql.sock


Changing the php.ini and my.cnf entries to match info.php and this script (and restarting MySQL and apache) immediateley fixed the problem !!

This is on:
Centos 4.0 (RHEL clone) with 2.6.9 kernel
Apache 1.3.33
PHP 4.3.10
Mysql 4.1.7
Xoop 2.2

Note that I had previously edited my.cnf and added the line
old_passwords
to the mysqld section prior to creating the MySQL user for Xoops.

Thanks everyone. This entire thread was invaluable !

al