>perl -e"print qq{\x03\x1A}" | perl -le"print uc unpack 'H*', <STDIN>"
031A

$perl -e'print qq{\x03\x1A}' | perl -le'print uc unpack "H*", <STDIN>'
031A


##</code><code>##

my @records = map parse_rec($_),
              map /(.{$RECSIZE})/sg,
              do { local $/; <$fh> };

##</code><code>##

my @records;
local $/ = \$RECSIZE;
local *_;
while (<$fh>) {
   push @records, parse_rec($_);
}

##</code><code>##

my @records;
local *_;
while (read($fh, $_, $RECSIZE)) {
   push @records, parse_rec($rec);
}