This is the name of the directory where template caches are
stored. By default this is
"./cache", meaning that
Smarty will look for the cache directory in the same directory
as the executing php script.
This directory must
be writeable by the web server
You can also use your own
custom cache handler
function to control cache files, which will ignore this
This setting must be either a relative or
absolute path. include_path is not used for writing files.
It is not recommended to put this directory under
the web server document root.