"Simple" echo/reading variable question...

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# 1  
Old 08-25-2011
"Simple" echo/reading variable question...

Hello, I have a simple(I think) question!
Although simple, I have been unable to resolve it, so I hope someone can help! OK, here it is:

1)I have an awk script that prints something, such as:
awk '{print $2}' a > x

so x might hold the value of say '10'

2)Now, I just want to check to see if this value is greater than 0
if [[ ($x -gt 0) ]]

however, the above statement does not work!
Similarily, when I type:
echo $x

I just get a blank line! How do I get $x to actually read my value of x? Thanks!!

Last edited by Franklin52; 08-25-2011 at 02:56 PM.. Reason: Please use code tags for data and code samples, thank you
# 2  
Old 08-25-2011
x=$(awk '{print $2}' a)
echo $x

This User Gave Thanks to itkamaraj For This Post:
# 3  
Old 08-25-2011
Much thanks!
# 4  
Old 08-25-2011
external utilities like awk/cut/sed are efficient when run on batches of data, but using them to operate on single lines is extremely wasteful. They take time to load and quit; imagine only being able to say one word per phone call.

To read and tokenize input from a file without awk, you can use the read builtin, which will be literally hundreds of times faster.

read A B C < file

which will attempt to split the line into at least three tokens. The line 'a b c d e f g' would get split into A='a', B='b', C='c d e f g'.
This User Gave Thanks to Corona688 For This Post:
# 5  
Old 08-25-2011
Corona, thank you very much! That's very useful Smilie
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