Well, that's a pretty general question, but a multi-step process. You'd first need to open the file, run through line by line, and then grab the value within the tags. Assuming your XML file would look something like this "<IP-NEIGHBOUR>192.168.1.1</IP-NEIGHBOUR>" then the code would be something like this: 
#!/usr/bin/perl
#
use strict;
use warnings;

# open file for reading
open ( XML, "/path/to/file" ) || die "Can't open file $!"

while ( <XML> ) {   # go through line by line
     $_ =~ ( /<IP-(ADDRESS|NEIGHBOUR)>(.+?)<\/IP.+?/ )
     my $ip = $2;  # IP is the value in 2nd parenthesis
}

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The essence of the problem lines with in the regular expression -- I'd suggest some reading up on them if you want to get serious with data extraction. Of course, the regex might change based on your XML file.

In reply to Re: Extracting tagged data from a XML file by GaijinPunch
in thread Extracting tagged data from a XML file by theroninwins

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