doc-src/System/misc.tex

     -r           reset session path
     -s NAME      override session NAME
 
   Build object-logic or run examples. Also creates browsing
   information (HTML etc.) according to settings.
+
+  ISABELLE_USEDIR_OPTIONS=
 \end{ttbox}
 
 Note that the value of the \settdx{ISABELLE_USEDIR_OPTIONS} setting is
 implicitly prefixed to \emph{any} \texttt{usedir} call. Since the
 \ttindex{IsaMakefile}s of all object-logics distributed with Isabelle