use strict; 
use warnings; 
use IO::File; 
use Slurp; 
 
 
my $master_file = '.\db\MASTER_DATA.csv'; 
my $number_toscan = 100; 
 
my @all_master_data = Slurp::to_array($master_file) or die; 
my $file_start = IO::File->new('START.csv', 'w'); 
 
foreach (@all_master_data[0 .. ($number_toscan -1)]) { 
	$file_start->print($_); 
}

  #!/usr/bin/perl   
use strict;   
use warnings;   
use Tie::File;   
  
my $master_file = '.\db\MASTER_DATA.csv';   
my $new_file = 'START.csv';   
#my $number_to_scan = 100;   
  
tie my @array, 'Tie::File', $master_file or die "Unable to tie $master_file.\n$!";   
open my $new, ">", $new_file or die "Unable to open $new_file for writing.\n$!";   
  
print $new splice @array, 0, 100;   
  
untie @array or die $!;   
close $new or die $!;