I have no idea what your code is doing, but take a look at the following redo. Hopefully it will help. 
#!/usr/bin/perl
                                                                      
my $filename ="./multipath.tr";
my $sim_time;
my $recv = 0;
                                                                      
open(FILE, "<$filename") || die "file $filename can't open : $!";
                                                                      
while(<FILE>) {
  chomp;
  my @entry = split /\s+/;
  print scalar(@entry), "\n";
  next unless (scalar(@entry) == 51);
  get_throughput(\@entry);
} 

close FILE;

print $recv, "\n";

sub get_throughput {
  my $entry = shift;

  # do you really need all this?
  # don't seem to be doing anything
  # with them.
  my ($node_id, $end_point, $flow_id, $pkt_id); 
                                                
                                                
  
  if($entry->[1] eq "r") {
    $sim_time  = $entry->[3];
    $node_id   = $entry->[5];
    $end_point = $entry->[39];
    $pkt_id    = $entry->[41];

    # this is the 38th col. Use element 36 instead.
    $recv     += $entry->[37];  
  }
}

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In reply to Re: What's wrong with my code? [from a beginner] by punkish
in thread What's wrong with my code? [from a beginner] by Wordlover

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