#!/usr/bin/perl

use strict;
use Tie::File;
use Getopt::Long;
use vars qw($opt_I);

my $file = "/proc/net/dev";
my $new_in_bytes=0;
my $new_out_bytes=0;
my $completestring;
my @splitinterface;
my @dataset_in;
my @dataset_out;
my @dataset_out_split;

Getopt::Long::Configure('bundling');
GetOptions
	("I=s" => \$opt_I, "Interface" 	=> \$opt_I);


open(my $FH, $file) or die "$!\n";
while (<$FH>){
	$completestring = $_ if ($_=~ /$opt_I/);
	@splitinterface = split(/:/,$completestring,2);
	@dataset_in = split(/ /,@splitinterface [1]);
	$new_in_bytes = @dataset_in[0];
	@dataset_out = split(/0 /,@splitinterface [1]);	

	if (@dataset_out[6] =~ '\s') {
		@dataset_out_split = split(/\s/,@dataset_out[5]);
		$new_out_bytes = @dataset_out_split[5];
		print "\n@dataset_out_split\n";
	} else {
		$new_out_bytes = @dataset_out[6];
	}
}
	#print "$new_in_bytes\n$new_out_bytes\n";