CTLFLG
 
     CTLFLG is a logical flag which indicates whether control characters 
     are included in a raw surface data set to be decoded.  

     The raw surface data set must contain either bulletins from the 
     Domestic Data Service or single station reports.  If the data set 
     contains bulletins, set CTLFLG = YES.  Otherwise, it will be
     assumed that the file contains single station reports with one
     report per line.
     
     If CTLFLG = YES, the input file must contain bulletins.  If
     CTLFLG = NO, the file must have reports.