m.dem.extract from disks, new info

Michael Shapiro shapiro at zorro.cecer.army.mil
Mon Aug 24 15:06:47 EDT 1992

The m.dem.extract program on moon.cecer.army.mil which attempt to
read  DEM data from disk files as well as tapes requires that the
disk file NOT have any special characters added to the  file.  In
particular,  utilities  that copy tape to disk often add carriage
returns or line feeds (or both). If your utility does  add  these
characters,  here  is  a  one  line shell script that will remove

fold $* | sed 's/^M/g' | awk '{printf("%s",$0)}'

Please note the the ^M is  supposed  to  be  a  single  character
(carriage  return).   It appear here as 2 characters (and here it
is in fact 2 characters). You will have to edit the ^M and put  a
real  control-M in their place. In vi this can be done by deleted
the ^M and  inserting  a  true  RETURN  by  typing  in  control-V

We will  fix  m.dem.extract  to  ignore  linefeeds  and  carriage
returns  so this won't be necessary in the future. But the script
is useful for later programs  that  attempt  to  deal  with  disk
images   of   tapes   that   do   not  account for these inserted
carriage returns and linefeeds.


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