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assignment to variable from eval command


 
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# 1  
assignment to variable from eval command

Hi Gurus,

I am having 2 parameters as below

parm1=value1
parm2=parm1

I want to evaluate parm1 value using eval echo \$$parm2 and later i want to assign this value to other variable which i will be using in if statement like :

if [[ $var=='value1 ]]; then
do this.......
fi

could you please suggest some way as I am not able to achieve this.
# 2  
Try...
Code:
eval var=\$$parm2

# 3  
Thanks a lot

It worked for me !!

---------- Post updated at 03:07 PM ---------- Previous update was at 02:52 PM ----------

One more thing Ygor,

Its working when I am executing from command line, but same is not working when I am putting it in to a script :

Code:
for prm in RUN_COST_PRICES_COMPARISON RUN_SELLING_PRICE_COMPARISON RUN_RATIO_PACK_COMPARISON
>     do
>     echo $prm
>     eval VAR=\$$prm
>     echo $VAR
> done
RUN_COST_PRICES_COMPARISON
Y
RUN_SELLING_PRICE_COMPARISON
N
RUN_RATIO_PACK_COMPARISON
Y

But when the same thing kept in the script eval command is not working.

Code:
./aa
RUN_COST_PRICES_COMPARISON

RUN_SELLING_PRICE_COMPARISON

RUN_RATIO_PACK_COMPARISON

Could you pleases advice if something needs to be added

---------- Post updated at 03:33 PM ---------- Previous update was at 03:07 PM ----------

Quote:
Originally Posted by k_vikash
Thanks a lot

It worked for me !!

---------- Post updated at 03:07 PM ---------- Previous update was at 02:52 PM ----------

One more thing Ygor,

Its working when I am executing from command line, but same is not working when I am putting it in to a script :

Code:
for prm in RUN_COST_PRICES_COMPARISON RUN_SELLING_PRICE_COMPARISON RUN_RATIO_PACK_COMPARISON
>     do
>     echo $prm
>     eval VAR=\$$prm
>     echo $VAR
> done
RUN_COST_PRICES_COMPARISON
Y
RUN_SELLING_PRICE_COMPARISON
N
RUN_RATIO_PACK_COMPARISON
Y

But when the same thing kept in the script eval command is not working.

Code:
./aa
RUN_COST_PRICES_COMPARISON

RUN_SELLING_PRICE_COMPARISON

RUN_RATIO_PACK_COMPARISON

Could you pleases advice if something needs to be added
Can someone please help me on this. Thanks
# 4  
bash code:
  1. for prm in RUN_COST_PRICES_COMPARISON RUN_SELLING_PRICE_COMPARISON RUN_RATIO_PACK_COMPARISON
  2. do
  3.      echo $prm
  4.      echo ${!prm}
  5. done
Are the variables filled in your script?
to verify, add this to the the previous one:
Code:
echo "before expansion"
echo $RUN_COST_PRICES_COMPARISON
echo $RUN_SELLING_PRICE_COMPARISON
echo $RUN_RATIO_PACK_COMPARISON
echo "------------------"

# 5  
Hi,

I am using ksh version, so this is failing with below error :


./aa[8]: ${!prm}: 0403-011 The specified substitution is not valid for this command.
# 6  
It works fine for me with the same script you use..
Code:
RUN_COST="Y"
RUN_SELLING="N"
RUN_RATIO="Z"

for prm in RUN_COST RUN_SELLING RUN_RATIO
do
     echo $prm
     eval VAR=\$$prm
     echo  "$VAR"
done

Ouyput:
RUN_COST
Y
RUN_SELLING
N
RUN_RATIO
Z

Are the RUN_COST*..etc have values assigned in the script? Or try as echo "$VAR"

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