#! perl -slw
use strict;

open IN, '+<', $ARGV[0] or die $!;
my @splits;

my $pos = 0;
while( <IN> ) {
	$splits[ unpack 'n', substr( $_, 0, 2) ] .= 
          pack( 'V', $pos ) . substr $_, 2, 4;
	$pos = tell IN;
}

@splits = grep $_, @splits;

my $n;
for my $split ( @splits ) {
	$split = join'', map{ substr $_, 0, 4 } sort{
		my( $as, $at, $bs, $bt ) = ( unpack( 'VA4', $a ), unpack( 'VA4', $b ) );
		$at cmp $bt
		||
		do{ seek IN, $as, 0; scalar <IN> }
		cmp
		do{ seek IN, $bs, 0; scalar <IN> }
	} unpack '(A8)*', $split;
}

for my $split ( @splits ) {
	printf do{ seek IN, $_, 0; scalar <IN> } for unpack 'V*', $split;
}