Pattern matching in Perl

Shell Programming and Scripting
1

Hi,

I have a list of IP, eg :

192.168.0.15
192.168.0.24
192.168.2.110
192.168.2.200

And I would like the shortest pattern who match with '192.168.0' and '192.168.2' (without the last dot and number).

2 
perl -lane 'print $_ if $_=~/192.168.[02]/' filename.txt
3 
grep '^192\.168\.[02]\.' file

or

grep -w '^192\.168\.[02]' file
4

Thanks itkamaraj,

To be honest i'm not very familiar with Perl in command line, I intended to use grep.
And i'm searching for something very generic, because I won't to read first numbers each time.

Something like this:

grep -P '\d+\.\d+\.\d+' filename.txt

My question is there a simpler pattern for this ?
Is possible to repeat some part of the pattern, for example: '\d+' x3 and '\.' x2

5

Like this?

grep -E '[0-9]{3}\.[0-9]{3}\.[02]\.' inputfile
6

Yes thanks that's the idea, but the question it's for Perl regex not POSIX.

7

Like this?

(\d{1,3}\.){3}

or this?

(\d+\.){3}
8

Yes, except that the part of IP should end with a number not a dot.