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expr in shell programming


 
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# 1  
Old 11-30-2007
expr in shell programming

i am new to shell programming, currently using redhat linux of version
2.4.20-8.
i have problem in executing expr command in the following shell script

$ x=5
$ x='expr $x + 1'
$ echo $x

the output is displaying always
expr $x + 1

Pls guide me for the above query
# 2  
Old 11-30-2007
Use

`expr $x + 1`

use the symbol on that is on "~" on your key board
# 3  
Old 11-30-2007
I prefer to avoid "expr":

Code:
x=5
((x+=1))
echo $x


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