Yes, toolic is right, chomp is needed to remove the new line character from the input line, but the other change proposed by vinoth.ree is also needed, because, right now, this line of your code: 
next if $. < 2;

[download]
is skipping the two first lines, whereas your IP address sits on the second line, so that the is_ipv4 subroutine never gets a chance to see it. Changing it to: 
next if $. <= 2;

[download]
or something equivalent would solve this issue.

Actually, rather than skipping lines, which is not very robust (your file might have a commented-out line at the top, who knows?), I would rather check if the extracted key matches IPADDR.

Je suis Charlie.

In reply to Re: IP address validation when IP is picked dynamically by Laurent_R
in thread IP address validation when IP is picked dynamically by rahulruns

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