regex to match an ip

echo | grep -P '^((25[0-4]|2[0-4]\d|[01]?[\d]?[1-9])\.){3}(25[0-4]|2[0-4]\d|[01]?[\d]?[1-9])$'
This obey that you don't match any broadcast or network addresses and stay between -

By: foob4r
2009-09-17 12:59:44

3 Alternatives + Submit Alt

What Others Think

Doesn't handle, which is a valid address.
arcege · 666 weeks and 6 days ago
How do you know what the network and broadcast addresses are without knowing the network mask? If you're on, then and are both valid addresses.
andrew112358 · 666 weeks and 6 days ago
The combo of the leading ^ and the trailing $ will force the regex to match an IP address on a line all by itself, so this will not match IPs embedded in text.
bwoodacre · 666 weeks and 5 days ago
ok u'r right @andrew112358 i only thought about /24
foob4r · 666 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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