Returns a persistent variable.
Case-sensitivity of the variable_* functions depends on the database collation used. To avoid problems, always use lower case for persistent variable names.
$name: The name of the variable to return.
$default: The default value to use if this variable has never been set.
The value of the variable. Unserialization is taken care of as necessary.
function variable_get($name, $default = NULL) {
global $conf;
return isset($conf[$name]) ? $conf[$name] : $default;
}