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How to get an Indirect Variable Value..?

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Operating Systems Linux How to get an Indirect Variable Value..?
# 1  
Old 03-12-2010
How to get an Indirect Variable Value..?
Hi,

I've got a small problem.

If varible A stores "B" and Variable B stores C,
How to get the value of variable B by using only Variable A..?

I tried the following but didnt work pease help..

Code:
 
$ var1=vikram
$ echo $var1
vikram
$ vikram=sampath
$ echo $vikram
sampath
$ echo $`echo $var1`
$vikram

In the above code
Why i'm getting "$vikram" when i was expecting "sampath" (because $vikram=sampath)

Please help me the right way to decode in the above situation..

thanks

Vikram shetty
# 2  
Old 03-12-2010
MySQL
See the following code.

Code:
 var1=vikram
 echo $var1
vikram=sampath
 echo $vikram
 eval echo \$$var1

[or]
Code:
 eval echo \$$(echo $var1)

[or]

Code:
   eval echo \$`echo $var1`

# 3  
Old 03-12-2010
Code:
eval result=\$$var1
echo $result

It will print the word sampath
# 4  
Old 03-12-2010
thanks u very much ungalnanbu and selvan..

Its working fine..

Could you please pass on me any material that describes the above behaviour of variables..

thanks

Vikram shetty
# 5  
Old 03-12-2010
Indirect References.
http://www.linuxjournal.com/article/7385
Please go through the above URL.
This will help you to know about variables.
Last edited by thillai_selvan; 03-12-2010 at 02:31 AM..
# 6  
Old 03-12-2010
MySQL
Refer the following links.

Advanced Bash-Scripting Guide
Very Simple Bash Scripts
Linux Shell Scripting Tutorial - A Beginner's handbook
# 7  
Old 03-12-2010
Thank you very much guys..

warm regards
Vikram Shetty
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