substitute variable in bash


 
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# 1  
Old 03-21-2011
substitute variable in bash

hi all,

Assume that i a having the following three lines in an executable file
Code:
#/bin/bash
a=Tue
Tue=1

When i give echo $a the value should be 1, how to do this. Your suggestions please.

Thanks in advance,
Anish

Last edited by Franklin52; 03-21-2011 at 04:56 AM.. Reason: Please use code tags
# 2  
Old 03-21-2011
You should initiate the Tue Variable before the a variable.

In your script, when you assign the Tue variable to a it has no value.
Your script should be like this :
Code:
#/bin/bash
Tue=1
a=Tue

# 3  
Old 03-21-2011
And since variable 'a' does not hold value as $Tue we add another $ in the below echo statement to print Tue's value.
Code:
eval echo \$$a

# 4  
Old 03-21-2011
Hi dude ,

The code which you posted is not working

echo $a given means it shows tue
# 5  
Old 03-21-2011
Quote:
Originally Posted by theboogymaster
You should initiate the Tue Variable before the a variable.
Code:
#/bin/bash
Tue=1
a=Tue

But:
Code:
#/bin/bash
Tue=1
a=${!Tue}

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