#!/usr/bin/perl
use strict;
use warnings;
use 5.010;

open  (TRACK1, ">", "track1.txt")  	or die "Can't open track1.txt : $!";
open  (TRACK2, ">", "track2.txt")  	or die "Can't open track2.txt : $!";
open  (TRACK3, ">", "track32.txt")  	or die "Can't open track3.txt : $!";

while (<>) {
    if(/name="track1/ .. /^1_000/){
    	print TRACK1;
    }
    elsif(/name="track2/ .. /^5_000/) {
    	print TRACK2;
    }
    elsif(/name="track3/ .. /^20_000/) {
    	print TRACK3;
    } #no 'else' here.
}