locate [--id|:i] xpath
Print canonical XPaths leading to nodes matched by a given xpath.
If flag --id (:i) is
used then ID-based shortcuts are allowed in the resulting
location paths. That means that if the node or some of its
ancestors has an ID attribute (either
xml:id or one specified in a DTD) then
the corresponding segment of the canonical location path
is replaced by the id() function
which jumps directly to an element based on its ID.