Read column from file and run commands with the values

Question

I have such textfile:

313 "88.68.245.12"
189 "87.245.108.11"
173 "84.134.230.11"
171 "87.143.88.4"
158 "77.64.132.10"
....

I want to grep only the IP from the first 10 lines, run whois over the IP adress and from that output I want to grep the line where it says netname.

How can I achieve this?

this is quite basic and has been asked repeatedly here. What did you try? — fedorqui, Jan 13 '15 at 14:07
Wow I dont think it is basic.. I am trying with awk and grep at the moment. — Stephan Kristyn, Jan 13 '15 at 14:07
`awk -F'"' '{print $2}' file | xargs whois | grep 'netname'` — Avinash Raj, Jan 13 '15 at 14:08
piping to whois says "Now whois server is known for this kind of object." — Stephan Kristyn, Jan 13 '15 at 14:10
@SirBenBenji you can use a `while read` loop and keep track of the lines you've read so far. — fedorqui, Jan 13 '15 at 14:17
You mean like this? `head -n 10 myFile | awk -F'"' '{print $2}' | while read -r file; do whois;` — Stephan Kristyn, Jan 13 '15 at 14:23
Give a read to this: http://stackoverflow.com/questions/13122441/how-do-i-read-a-variable-on-a-while-loop — fedorqui, Jan 13 '15 at 14:26

score 1 · Accepted Answer · answered Jan 13 '15 at 14:36

1

Just loop through the file with while - read:

while IFS='"' read -r a ip c
do
    echo "ip: $ip"
    whois "$ip" | grep netname
done < <(head -10 file)

This is giving IFS='"' so that the field separator is a double quote ". This way, the values within double quotes will be stored in $ip.

Then, we print the ip and perform the whois | grep thing.

Finally, we feed the loop with head -10 file, so that we just read the first 10 lines.

answered Jan 13 '15 at 14:36

fedorqui

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As an aside: I am trying to incorporate a sort feature in your script, but this is not working `done < <(head -10 file | sort)` – Stephan Kristyn Jan 13 '15 at 15:02
What are you trying to `sort`? The initial file or the output? If it is the output, just pipe everything *after* the whole block I posted. – fedorqui Jan 13 '15 at 15:03
TY for following up. Trying to sort the file which has around 1000 of lines then run the whois block on the first ten lines ot that output. – Stephan Kristyn Jan 13 '15 at 15:18
@SirBenBenji This is quite a different question and, for this, you should indicate desired output, etc. You'd better check some questions with [sort] and [bash] and also `man sort`. – fedorqui Jan 13 '15 at 15:29
Follow-up: http://stackoverflow.com/questions/27941781/bash-script-to-sort-input-file-before-piping-to-while-loop#27941781 – Stephan Kristyn Jan 14 '15 at 12:22

Read column from file and run commands with the values

1 Answers1