The $sourcepath variable is set at startup to the file (not
URL) path to the source of the Vortex script (not module) being
executed, including ".vs" extension if applicable. It is
similar to the $PATH_TRANSLATED variable set by most Web
servers, except state/function information has been stripped. The
$sourcepath variable was added in version 2.1.904540000
19980831. Note: this is deprecated in favor of <vxinfo
sourcepath>, which is more reliable as it cannot be overwritten as a
variable can.