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Join Date: Nov 2007
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Newbie Poster
Problem in expr 2+4 Dear friends ,
file is test.sh
its give result 2+4 not 6 so plz tell how can i get the right result
sanjay
file is test.sh
echo expr 2+4;
its give result 2+4 not 6 so plz tell how can i get the right result
sanjay
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Join Date: Oct 2007
Location: Cherry Hill, NJ
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What shell are you using. If it is bash or csh or somesuch, you need to use backquotes:
Hope this helps.
echo `expr 2+4`Hope this helps.
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Newbie Poster
Dear ,
I am using Bash shell and i did echo `expr 2+4`
but it give 2+4 not 6 ..
plz help me sir why its not working ???????????
sanjay
I am using Bash shell and i did echo `expr 2+4`
but it give 2+4 not 6 ..
plz help me sir why its not working ???????????
sanjay
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Join Date: Nov 2007
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Newbie Poster
Re: Problem in expr 2+4 Dear friends ,
i solved this problem by following ..........
echo `expr 2 + 4`
its give result 6 .we should give space between operator and operand
sanjay
i solved this problem by following ..........
echo `expr 2 + 4`
its give result 6 .we should give space between operator and operand
sanjay
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Join Date: Oct 2007
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Posting Whiz
With bash if you are typing on the command line you can just type
$ expr 2 + 4
6
If you are putting it in a file, you can do
#! /bin/bash
expr 2 + 4
var=`expr 2 + 4`
echo $var
and it will print:
6
6
$ expr 2 + 4
6
If you are putting it in a file, you can do
#! /bin/bash
expr 2 + 4
var=`expr 2 + 4`
echo $var
and it will print:
6
6
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Join Date: Oct 2007
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Posting Whiz
If you're using a more advanced shell than posix or sh, you can use "let" also - just a suggestion 
let var=2+4
echo $var
let works the opposite of expr, in so far as the spaces go - you shouldn't put any spaces between operators and operand
, Mike
let var=2+4
echo $var
let works the opposite of expr, in so far as the spaces go - you shouldn't put any spaces between operators and operand
, Mike
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Join Date: Feb 2006
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You can also, as long as it is not csh or sh, just simply do
var=$(( 2 + 4 ));
var=$(( $var + 2 ));
var=$(( 2 + 4 ));
var=$(( $var + 2 ));
Java Programmer and Sun Systems Administrator
----------------------------------------------
Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it.
--Brian Kernighan
----------------------------------------------
Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it.
--Brian Kernighan
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