Control

   The Control flag (.) is placed at the left margin to begin a
   string of DSR commands. When you want a period to be accepted as
   a text character, you do not need to precede it with an Accept
   flag (_) as long as the period is not placed at the left margin.
   If you do need to have a period in the 0 character position
   (and it is not part of a DSR command), you must precede it with
   an Accept flag. Alternatively, you can use two periods at the
   beginning of a line; the effect is the same as if you had used an
   Accept flag.
 

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