Substring extraction using bash shell scripting and awk

Posted by rohanbk on Stack Overflow See other posts from Stack Overflow or by rohanbk
Published on 2010-04-03T23:17:42Z Indexed on 2010/04/03 23:23 UTC
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bash

|

awk

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shell-scripting

So, I have a file called 'dummy' which contains the string:

"There is 100% packet loss at node 1".

I also have a small script that I want to use to grab the percentage from this file. The script is below.

result=`grep 'packet loss' dummy` |
awk '{  first=match($0,"[0-9]+%")
        last=match($0," packet loss")
        s=substr($0,first,last-first)
        print s}'

echo $result

I want the value of $result to basically be 100% in this case. But for some reason, it just prints out a blank string. Can anyone help me?

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