Pear Libraries for PHP are your friend

When using Pear, the pear config file in your home directory ($HOME/.pearrc) is your FRIEND. This little nugget of information will save your life one day.

To get config values in and out, use the $pear config-set option command.

ex.
$pear config-set download_dir $HOME/tmp


What the above does, is set the directory where files from the Pear repository will be downloaded. So if you're using a shared host, you need to set this along with the "temp_dir" setting as well. Burn this into your head if you work with PHP and Pear libraries! It'll save your life one day.