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Shell Programming and Scripting

Evaluating a variable

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# 1  
Old 10-03-2010
Evaluating a variable
Does anyone know of a way to force a variable name held in another variable to return the value of the first variable? Best if I give an example, that does not work:
Code:
/usr/local/bin >cat mike.sh
NUM1ref=16
NUM2ref=32
echo "=============="
for VAR in NUM1 NUM2
do
  XXXX=${VAR}ref
  echo $XXXX
  echo "=============="
done
/usr/local/bin >./mike.sh 
==============
NUM1ref
==============
NUM2ref
==============
/usr/local/bin >

I want this to echo the value held in NUM1ref (16), rather than the string "NUM1ref", so the variable XXXX has to be evaluated twice.

I hope that makes sense!
Last edited by Franklin52; 10-03-2010 at 10:33 AM.. Reason: Please indent your code and use code tags
# 2  
Old 10-03-2010
bash, how to get variable name from variable
# 3  
Old 10-03-2010
If you haven't got bash.

Code:
NUM1ref=16
NUM2ref=32
echo "=============="
for VAR in NUM1 NUM2
do
  eval echo \$${VAR}ref
  echo "=============="
done

==============
16
==============
32
==============

This User Gave Thanks to methyl For This Post:
mikejordan
# 4  
Old 10-04-2010
Thanks Methyl, that does it.
Out of interest, if I have got a bash shell ...?

Regards, Mike
# 5  
Old 10-04-2010
(See the link in bartus11 post - it shows the special syntax for bash).
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