Filter IPs out of files

egrep -o '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' file.txt

By: P17
2009-05-28 14:46:17

What Others Think

egrep -wo '([0-9]{1,3}\.){3}[0-9]{1,3}' file.txt selects on word boundaries and is slightly less verbose
kiwi · 624 weeks and 1 day ago
cool didn't know about the -o option ....
copremesis · 624 weeks and 1 day ago
perl version: perl -ne's/(\d{1,3}\.){3}\d{1,3}/print"$&\n"/ge' file.txt and, perl version (word boundary): perl -ne's/\b(\d{1,3}\.){3}\d{1,3}\b/print"$&\n"/ge' file.txt
wbx · 624 weeks and 1 day ago
This is all *plain wrong*, you extract 4 numbers (Each up to three digits) seperated by dots with these regexes. These numbers don't have to be valid IPs. See: echo "999.999.999.999" > file.txt echo "" >> file.txt perl -ne's/(\d{1,3}\.){3}\d{1,3}/print"$&\n"/ge' file.txt 999.999.999.999 egrep -o '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' file.txt 999.999.999.999 Better use sth. like that (Not mine, found with google): egrep '\b(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b' file.txt
OJM · 624 weeks 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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