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Filter IPs out of files

Terminal - 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
2009-05-28 14:46:17
User: P17
Functions: egrep
4
Filter IPs out of files

Alternatives

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Terminal - Alternatives

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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

Comment by kiwi 312 weeks and 1 day ago

cool didn't know about the -o option ....

Comment by copremesis 312 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

Comment by wbx 312 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 "10.1.12.23" >> file.txt perl -ne's/(\d{1,3}\.){3}\d{1,3}/print"$&\n"/ge' file.txt

999.999.999.999

10.1.12.23

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

999.999.999.999

10.1.12.23

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

10.1.12.23

Comment by OJM 312 weeks and 1 day ago

Your point of view

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