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You can't use foreach like this - you need to use while to make your code work. See the code below for a demo:

$data = <<'DATA'; foo 1.1.1.1 foo bar 22.22.22.22 bar baz 333.333.333.333 baz DATA # this is *wrong* foreach($data=~ /(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})/g){ push @ips, $1; } print "Foreach fails and gives:\n"; print "$_\n" for @ips; @ips = (); # this is right while($data=~ /(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})/g){ push @ips, $1; } print "While works and gives:\n"; print "$_\n" for @ips;

For an explanation of why the for loop generates three copies of the last IP address you need to consider what has happened. A /g type regex will return an array of matches. So as it is called in array context it returns an array (this actually contains the three addresses) however $1 now contains the last address matched as we had to match all occurences to generate the array. We then iterate over this array and push $1 (the last IP address) into our array three times. To fix this we either use while or push $_ (not $1) into our IP array like this:

$data = <<'DATA'; foo 1.1.1.1 foo bar 22.22.22.22 bar baz 333.333.333.333 baz DATA foreach($data=~ /(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})/g){ push @ips, $_; } print "Foreach now gives:\n"; print "$_\n" for @ips;

Oh you can slurp up the file into a variable $data like this:

open FILE, "<path/to/file" or die "Oops, Perl says: $!"; { local $/; $data = <FILE>; } close FILE;

cheers

tachyon

s&&rsenoyhcatreve&&&s&n\w+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print


In reply to Re: Re: Extracting IP addresses from a file... by tachyon
in thread Extracting IP addresses from a file... by Brian Matchick

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