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])$'

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

-1

By: arcege

2009-09-17 17:40:48

echo egrep IP grep regex ip address

3 Alternatives + Submit Alt

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
This is sample output - yours may be different.
0

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])$'

foob4r · 2009-09-17 12:59:44 7
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
This is sample output - yours may be different.
-1

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

salparadise · 2009-09-17 16:14:52 3
regex to match an ip

regex to match an ip Show Sample Output
This is sample output - yours may be different.
```
echo "23.23.12.24" | 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])'

23.23.12.24
```
-2

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])'

KeePon · 2009-09-17 12:17:32 5

What Others Think

rahimhh21 · 109 weeks ago

Perfecthomepugs · 100 weeks and 4 days ago

pugpuppies95 · 62 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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