use strict;
use warnings;
my ($sector,$path);
my @sectorOutputFiles;
my @fh;
$path="blah";
for($sector=0;$sector<12;$sector++){
    $sectorOutputFiles[$sector]=">".$path.$filenamefirstpart.$sector.".txt";
    open($fh[$sector],'>',$sectorOutputFiles[$sector])
	or die "Can't open sector filehandler for writing.\n";
}