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regex to match an ip

Terminal - regex to match an ip
echo 127.0.0.1 | egrep -e '^(([01]?[0-9]{1,2}|2[0-4][0-9]|25[0-4])\.){3}([01]?[0-9]{1,2}|2[0-4][0-9]|25[0-4])$'
2009-09-17 17:40:48
User: arcege
Functions: echo egrep
-1
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regex to match an ip

Handles everything except octets with 255. Ran through ip generator with variable octet lengths.

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Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
echo 254.003.032.3 | 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])$'
2009-09-17 12:59:44
User: foob4r
Functions: echo grep
Tags: IP grep regex ip address
0
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regex to match an ip

This obey that you don't match any broadcast or network addresses and stay between 1.1.1.1 - 254.254.254.254

Comments (4) | Add to favourites | Report as malicious
perl -wlne 'print $1 if /(([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]))/' iplist
2009-09-17 16:14:52
User: salparadise
Functions: perl
Tags: perl IP regex ip address
-1
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regex to match an ip

if you want to only print the IP address from a file.

In this case the file will be called "iplist" with a line like "ip address 1.1.1.1"

it will only print the "1.1.1.1" portion

Comments (0) | Add to favourites | Report as malicious
echo "123.32.12.134" | 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])'
2009-09-17 12:17:32
User: KeePon
Functions: echo grep
Tags: IP grep regex ip address
-2
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regex to match an ip

regex to match an ip

Show sample output | Comments (2) | Add to favourites | Report as malicious

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