#!/usr/bin/perl -w
use strict;
use Time::Local;
chdir "/var/spool/wt400/gateways/$ARGV[0]" or exit;
mkdir "capture", 0755 unless (-d "capture");
my $Dir = $ARGV[1];
my $ListTime = 0;
my $BufferSize = 64 * 1024;
my $MaxLen = 0;
my %Traps;
my @GrepList;
my $GrepString;
my $Counter = 1;
my $Size;
my $Prev;
my $Now;
my $NF;

while (1) {
 if ($Counter > 20 || ! @GrepList) {
  if ( (stat("traplist.$Dir"))[9] gt $ListTime ) {
   $ListTime = (stat(_))[9];
   open (LIST,"traplist.$Dir");
   while (<LIST>) {
    next if ($_ =~ /^Created\t\tExpires/ || $_ =~ /^ *$/);
    my @Fields = split "\t" , $_;
    my($mon, $day, $year, $hour, $min) = split ?[-/:]? , $Fields[1];
    my $Expiration =  timelocal(0, $min, $hour, $day, $mon -1, $year +
+ 100);
    $Traps{"$Fields[6]"} = [ $Expiration,$Fields[2],$Fields[5],$Fields
+[7] ];
}
   close (LIST);
  }
 }

 @GrepList = ();
 $Now = time;
 foreach my $trap (keys %Traps) {
  push @GrepList,$Traps{$trap}[3] unless (($Traps{$trap}[0] < $Now && 
+$Traps{$trap}[1]) || $trap eq "SIZE");
 }
 map { $MaxLen = length($_) if length($_) > $MaxLen } @GrepList;
 $BufferSize = 2 * $MaxLen if ($BufferSize < 2 * $MaxLen);
 if (exists $Traps{"SIZE"} && $Traps{"SIZE"}[1]) {
  $Size = $Traps{"SIZE"}[2] unless ($Traps{"SIZE"}[0] < $Now && $Traps
+{"SIZE"}[2] > 0);
 }
 exit unless (@GrepList || $Size);

 $GrepString = join '|', map quotemeta $_, @GrepList;
 $GrepString = qr/($GrepString)/i;

 if ($Dir eq "out") {
  @ARGV = <out/do*>;
 }
 elsif ($Dir eq "in") {
  @ARGV = <in/di*>;
 }
 else {
  @ARGV = <out/do* in/di*>
 }
 
 if (@ARGV) {
  $/=\$BufferSize;
  $Prev= "";
  while (<>) {
   $_ =~ tr/\n//d;
   if(($Prev.$_) =~ /$GrepString/) {
    ($NF = "$ARGV-$+") =~ s/^.*\///;
    rename $ARGV , "capture/$NF";
    close (ARGV);
    $Prev = "";
   }
   if (eof) {
    $Prev = "";
   }
   else {
    $Prev = substr($_,-$MaxLen);
   }
  }
 }
 $/ = "\n";
 ++$Counter;
 sleep 3
}
[download]

This provides 10X more functionality the original shell script did.
I would appreciate any advice on how it could be made to go faster and still be efficient.

L~R