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How to evaluate the value of a variable ?

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# 1  
Old 08-11-2011
How to evaluate the value of a variable ?
How to evaluate the value of a variable ?
For example:

a=var
$a=value !!!error happens!!!

I want to evaluate var=value, how to realize it?
Thanks!

---------- Post updated at 03:37 AM ---------- Previous update was at 02:22 AM ----------

I am using linux bash.
Code:
a=var
$a=value !!!error happens!!!

I want the following result:
Code:
$echo $a
var
$echo $var
value

So I want the value of $a to be a variable, and it can be valued.
# 2  
Old 08-11-2011
Do you mean this?

Code:
$ a=var
$ var=value
$ eval echo \$$a
value
$

# 3  
Old 08-11-2011
Sorry,
Code:
[river@localhost ~]$ a=var
[river@localhost ~]$ echo $a
var
[river@localhost ~]$ $a=value
bash: var=value: command not found...

May be a=var1 , or a=var2
I just want evaluate the content of $a, not evaluate directly, but through $a.
For example:
Code:
a=var1
$a=value      ** assume it is a right command**

so I want
Code:
echo $var1
value

But
Code:
$a=value

is not a right command.Smilie
# 4  
Old 08-11-2011
Code:
$ a=var1
$ eval $(echo $a=value)
$ echo $var1
value

# 5  
Old 08-11-2011
Solved!!
Thanks for your help!
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