This bit of code is what I like to use to check the validity of an IP address.

This is a variation of one from the the Great Book "Mastering Regular Expressions" by Jeffrey Friedl,
which I highly recommend.

unless
(
    $ip =~ m/^(?:[1]?\d\d?|2[0-4]\d|25[0-5])\.
              (?:[1]?\d\d?|2[0-4]\d|25[0-5])\.
              (?:[1]?\d\d?|2[0-4]\d|25[0-5])\.
              (?:[1]?\d\d?|2[0-4]\d|25[0-5])$
            /x
)
{
    # do something
}

[download]
This catches everything except for '0.0.0.0' ip's

which you can handle easily by one addtional check to your test routine. 

if ( $ip =~ /^0.0.0.0$/ )
{
    # do something
}

[download]
Best Regards,
Wonko

In reply to Re: IP Address Sanity by Wonko the sane
in thread IP Address Sanity by Anonymous Monk

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