@ the "fossil http" or "fossil server" commands then add
    @ a command-line option "--errorlog <i>FILENAME</i>" to that
    @ command.
    @ </ol>
    style_finish_page();
    return;
  }
  if( P("truncate1") && cgi_csrf_safe(2) ){
    fclose(fopen(g.zErrlog,"w"));
  }
  if( P("download") ){
    Blob log;
    blob_read_from_file(&log, g.zErrlog, ExtFILE);
    cgi_set_content_type("text/plain");
    cgi_set_content(&log);
    return;
  }
  szFile = file_size(g.zErrlog, ExtFILE);
  if( P("truncate") ){
    @ <form action="%R/errorlog" method="POST">
    login_insert_csrf_secret();
    @ <p>Confirm that you want to truncate the %,lld(szFile)-byte error log:
    @ <input type="submit" name="truncate1" value="Confirm">
    @ <input type="submit" name="cancel" value="Cancel">
    @ </form>
    style_finish_page();
    return;
  }