I would build a hash of hashes. hash of hashes of hashes if you're gathering more than one segment of the snmp data. of course, CPAN is always a first choice but this would work in a pinch. 
#!/usr/bin/perl

use strict;

my %users;

while (<DATA>) {
        $users{$1}{$2}=$3 if /1\.1\.5\.1\.\d\.(\d)\ (\w+)\ (\w+)/;
}

use Data::Dumper;
print Dumper(%users);

__DATA__
13 1.3.6.1.4.1.546.1.1.5.1.1.1 INTEGER 1
13 1.3.6.1.4.1.546.1.1.5.1.1.2 INTEGER 2
13 1.3.6.1.4.1.546.1.1.5.1.1.3 INTEGER 3
13 1.3.6.1.4.1.546.1.1.5.1.1.4 INTEGER 4
13 1.3.6.1.4.1.546.1.1.5.1.2.1 OctetString user
13 1.3.6.1.4.1.546.1.1.5.1.2.2 OctetString user
13 1.3.6.1.4.1.546.1.1.5.1.2.3 OctetString user
13 1.3.6.1.4.1.546.1.1.5.1.2.4 OctetString user
13 1.3.6.1.4.1.546.1.1.5.1.3.1 OctetString pts/2
13 1.3.6.1.4.1.546.1.1.5.1.3.2 OctetString pts/3
13 1.3.6.1.4.1.546.1.1.5.1.3.3 OctetString pts/4
13 1.3.6.1.4.1.546.1.1.5.1.3.4 OctetString pts/5
13 1.3.6.1.4.1.546.1.1.5.1.4.1 INTEGER 10096
13 1.3.6.1.4.1.546.1.1.5.1.4.2 INTEGER 11928
13 1.3.6.1.4.1.546.1.1.5.1.4.3 INTEGER 4
13 1.3.6.1.4.1.546.1.1.5.1.4.4 INTEGER 21612
13 1.3.6.1.4.1.546.1.1.5.1.5.1 TimeTicks 11d 07:39:59
13 1.3.6.1.4.1.546.1.1.5.1.5.2 TimeTicks 9d 05:47:57
13 1.3.6.1.4.1.546.1.1.5.1.5.3 TimeTicks 14d 03:29:03
13 1.3.6.1.4.1.546.1.1.5.1.5.4 TimeTicks 0d 00:29:52
13 1.3.6.1.4.1.546.1.1.5.1.6.1 OctetString machine.domain.com
13 1.3.6.1.4.1.546.1.1.5.1.6.2 OctetString machine.domain.com
13 1.3.6.1.4.1.546.1.1.5.1.6.3 OctetString machine.domain.com
13 1.3.6.1.4.1.546.1.1.5.1.6.4 OctetString machine.domain.com

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In reply to Re: Parsing SNMP output by bageler
in thread Parsing SNMP output by Anonymous Monk

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