my @field_names = qw|PIIN FSCM N/A U/I UNIT PRICE AWD DT QTY OPT DT FOB REP TYPE|;
my $pack_defn   = 'A21 A9 A9 A2 A14 A8 A9 A9 A4 A5 A6';
my %fields;
@fields{@field_names} = unpack($pack_defn,$_);
foreach (@field_names){   
  print "\t$_\t\= " , $fields{$_},"\n";
}