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Adding Record Delimiters

LULC and Native format DEM and DLG data do not contain record delimiters. In most cases you will need to add them before using display programs. Once you down load the files you can add delimiters using the following UNIX command lines:

      1:250,000-scale Digital Elevation Models (DEM):
          dd if=inputfilename of=outputfilename ibs=4096 cbs=1024 conv=unblock 

      Digital Line Graph (DLG) data:
         Optional Format: 
          dd if=inputfilename of=outputfilename ibs=8000 cbs=80 conv=unblock 
         Standard Format: 
          dd if=inputfilename of=outputfilename ibs=8064 cbs=144 conv=unblock 
         SDTS Format:
          not applicable

      Land Use and Land Cover (LULC) data
          dd if=inputfilename of=outputfilename ibs=8000 cbs=80 conv=unblock