my @machines=("host1","host2","host3");
my %macs=();

for my $machine (@machines) {
  my $macraw=`getmac $machine`;
  if ($macraw =~ /(match something)/) {
    $macs{$1}=$machine;   
  }  
}

print "$macs{$_} $_\n" for (keys %macs);


##</code><code>##

Transport Address  Transport Name
-----------------  --------------
00-00-00-00-00-00  \Device\NetbiosSmb
00-A0-B0-6C-38-D0  \Device\NetBT_El90x1