- <option>OWNER</option> and <option>GROUP</option> fields support simple
- printf-like string substitutions:</para>
+ <option>OWNER</option>, <option>GROUP</option> and <option>RUN</option>
+ fields support simple printf-like string substitutions. The <option>RUN</option>
+ format chars gets applied after all rules have been processed, right before the program
+ is executed. It allows the use of the complete environment set by earlier matching
+ rules. For all other fields, substitutions are applied while the individual rule is
+ being processed. The available substitutions are:</para>