Cut Command, couple of examples

Had to do some more nice text manipulation this week following on sort of from examples about removing the lines beginning with a # etc.

I wanted to pull out just the IP addresses from the file so I could write something to ping the servers so knew what was up and what was already dead.

There was a lot of rubbish at the end of the lines, it looked like it was a tab as the delimiter after the IP address, so first off

$ cat dns_list.txt | cut -f1 -d$'\t' > dns1_list.txt

This did not clean it all up as some was not, so I decided to just pull out the first 15 characters that is the maximum the ip address would be.

$ cat dns1_list.txt | cut -b 1-15 > dns_list.txt

Then from there I had my list of IP addresses which I could then run some simple python code against to check if they are available.

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