while (<FILE>) {
   if ($ban_gate==1) {
      if ($_=~/END_BANNER/) {
         # found end of section, do stuff and turn off section processing
         $ban_gate=0;
      }
      else {
         # process a line in the banner section
      }
   }
   else {
      if ($ras_gate==1) {
         if ($_=~/END_xxxx/) {
            # found end of section, do stuff and turn off section processing
            $ras_gate=0;
         }
      }
      else {
         # process a line in the ras section
      }
   }
}