You probably have an older perl that does not understand the /r

Here's an alternate... 

#!/usr/bin/perl -l

# http://perlmonks.org/?node_id=1168769

use strict;
use warnings;

my %ips;

while(<DATA>)
  {
  /.* (\S+):(\S+)$/ or next;
  $ips{$1}{$2}++;
  }

for my $who ( sort keys %ips )
  {
  print $who;
  my @ips;
  for my $ip ( @ips = sort keys %{ $ips{$who} } )
    {
    print "=> $ip ($ips{$who}{$ip})";
    }
  print $who =~ /(.*?)\@/, " total: ", scalar @ips, " unique ip's\n";
  }

__DATA__
Jul 28 13:42:27 mail vpopmail[47985]: vchkpw-smtp: (PLAIN) login succe
+ss joe@example.com:192.168.250.251
Jul 28 13:42:28 mail vpopmail[47992]: vchkpw-smtp: (PLAIN) login succe
+ss joe@example.com:192.168.5.23
Jul 28 13:42:29 mail vpopmail[47994]: vchkpw-smtp: (PLAIN) login succe
+ss sally@example.com:192.168.10.28
Jul 28 13:42:27 mail vpopmail[47985]: vchkpw-smtp: (PLAIN) login succe
+ss fred@example.com:192.168.8.8
Jul 28 13:42:28 mail vpopmail[47992]: vchkpw-smtp: (PLAIN) login succe
+ss joe@example.com:192.168.5.23
Jul 28 13:42:29 mail vpopmail[47994]: vchkpw-smtp: (PLAIN) login succe
+ss harry@example.com:192.168.10.5

[download]

In reply to Re^3: How to parse a file with emails and IP's and output a sorted list with a total count by Anonymous Monk
in thread How to parse a file with emails and IP's and output a sorted list with a total count by mitzyc

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