bash scripting question

[Tyler Smith <tyler.smith@mail.mcgill.ca>]

Hi,

I've got a question about a short bash script I wrote. I need it to
loop over a number of names, and pass a command to grass that includes
two variations of those names. That was easy. Harder was getting
getting a letter included in each iteration, starting with A for the
first one and going up by one each iteration. What I came up with,
with extra bits snipped, is:

#!/bin/bash

lab_num=41

for map_name in aest_90 bush_90 carol_90 comp_90 \
    hirs_90 roan_90 swan_90 vir_90 ; 

  do

  lab_let=$(echo -n $(printf "\\x$(echo $lab_num)"))

  echo "
  $lab_let
  $map_name
  ${map_name}.ps" ;

  echo $((lab_num++)) > /dev/null ;

  done

The multi-line echo is passing instructions to a GRASS command, and in
the full script it works fine. This example runs fine without grass as
a demonstration. What I'm wondering about is the line:

  lab_let=$(echo -n $(printf "\\x$(echo $lab_num)"))

This was the only way I could figure out to loop from A to H. But
since it works on hex escape codes, it won't work past 9. Is there a
cleaner, more general way to do this?


Thanks,

Tyler