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Bash variable within variable

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Top Forums Shell Programming and Scripting Bash variable within variable
# 8  
Old 12-01-2014
You can reduce the two loops by one loop,
and the ! must prefix the bare variable name.
Code:
for I in P{{101..132},{200..209}}{A1,A2,B1,B2}
do
 echo cp "SRC_${!I}" "DES_${!I}"
done

---------- Post updated at 07:19 PM ---------- Previous update was at 07:05 PM ----------

The following assembles new variable names first, so their bare names can be used:
Code:
...
do
 SRC="SRC_$I"; DES="DES_$I"
 echo cp "${!SRC}" "${!DES}"
done

This User Gave Thanks to MadeInGermany For This Post:
yifangt
# 9  
Old 12-02-2014
echo cp "SRC_${!I}" "DES_${!I}" but SRC_${!I} did not expand as wanted.
Must remember this way!assembles new variable names first, so their bare names can be used!
Thanks a lot!
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