regex to match an ip

echo "" | grep -P '([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])'
regex to match an ip
Sample Output
echo "" | grep -P '([01]?\d?\d|2[0-4]\d|25[0-5])\.([01]?\d?\d|2[0-4]\d|25[0-5])\.([01]?\d?\d|2[0-4]\d|25[0-5])\.([01]?\d?\d|2[0-4]\d|25[0-5])'

By: KeePon
2009-09-17 12:17:32

3 Alternatives + Submit Alt

What Others Think

slightly less typing -- save 2 repetitions of the number-matching clause echo "" | grep -P '(([01]?\d\d?|2[0-4]\d|25[0-5])\.){3}([01]?\d\d?|2[0-4]\d|25[0-5])'
daithif · 618 weeks and 5 days ago
@daithif but this will also match what is invalid. to match correct and save expressions use: 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])$'
foob4r · 618 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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