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About storing the value of wc -l into a variable and then using this value in while


 
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# 1  
Old 05-04-2009
About storing the value of wc -l into a variable and then using this value in while

Hi all,

I m new to this forum.
I ma facing onei issue.

I have something like this:
length= wc -l < b2| awk '{print $1}'
where b2 is filename having detauls like:
cat b2
abc1
abc4
xyc3
sbdghf4

but when I do echo "$length" it displays nothing
Also I am using awk to overcome blanks in outut of wc -l < b2

Please guide...

# 2  
Old 05-04-2009
Please use [code][/code] tags for source.

First, wc wont print the filename if it's reading from stdin, so you would only need awk if you'd call it as
Code:
wc -l b2

Second, with variable assignments, whitespaces around '=' aren't allowed.
Third, what you're looking for are the backticks (`<command>`), or $(<command>), both will capture the output to be assigned to a variable.
# 3  
Old 05-04-2009
Quote:
Originally Posted by student2009
Hi all,

I m new to this forum.
I ma facing onei issue.

I have something like this:
length= wc -l < b2| awk '{print $1}'
where b2 is filename having detauls like:
cat b2
abc1
abc4
xyc3
sbdghf4

but when I do echo "$length" it displays nothing
Also I am using awk to overcome blanks in outut of wc -l < b2

Please guide...

Try
Code:
length=`wc -l < b2 | awk '{print $1}'`
echo $length

Thanks
NT
# 4  
Old 05-04-2009
Code:
length=`wc -l < b2 | tr -d ' '`

or
Code:
length=`awk 'END{print NR}' b2`

# 5  
Old 05-06-2009
Bug Thanks everyone. Its working now... I dont know how to close this thread...

Quote:
Originally Posted by danmero
Code:
length=`wc -l < b2 | tr -d ' '`

or
Code:
length=`awk 'END{print NR}' b2`


Thanks everyone. Its working now... I dont know how to close this thread...

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