\const{HTCEXT}{htc htx html}
\const{SKIPDIR}{sys htc SCCS}
\def{tree.update}{}{
  [xmod:=\now];
  \ldef{trav}{x}{
    \staturi{\1}{
      \if(count stat.ALIAS)(@<-stat.);
      \forall{it}{\dirent{\1}}{
        \if(\dirmod(it)&24576){
          \nif(\SKIPDIR which (it past \1)){\trav{[it]/}}
        }{
          \if(\HTCEXT which (it rpast ".")){
            \staturi(it){\if(count stat.ALIAS)(@<-stat.)}
          }
        }
      }
    }
  };
  \db{TREE}{\trav{/}\query(XMOD<xmod){\rem.rec}}
}