use constant BLOCKHDR => 28;
use constant BLOCKDATA => 4;
use constant CDRLENGTH => 286*3;
use constant BLOCKLEN  => BLOCKHDR + BLOCKDATA + CDRLENGTH;

if ($fname) {
        open (OUTPUT, ">$fname.tmp");
        open (DATA, "$fname");
        binmode DATA;
        $offset = 0;
        while (read(DATA, $data, BLOCKLEN, $offset)) {
                my $blockhdr = unpack "H*", substr($data, 0, BLOCKHDR);
                my $blockdt  = unpack "H*", substr($data, BLOCKHDR, BLOCKDATA);
                my $cdrdata  = unpack "H*", substr($data, BLOCKHDR+BLOCKDATA, CDRLENGTH);

                my $total_record = hextoint(reverse_str(substr($blockdt,4)));
                print "TEST $offset\n";

                if ($total_record eq 3) {
                        #printf (OUTPUT "%s", pack("H*", $blockhdr . $blockdt . $cdrdata));
                        $offset += BLOCKLEN;
                        #printf ("%s\n", $blockhdr . $blockdt . $cdrdata);
                        printf ("TEST1: $t_cdr - $offset - $blockhdr - $blockdt\n");
                } else {
                        #printf (OUTPUT "%s", pack("H*", $blockhdr . $blockdt . $cdrdata . DUMMYCDR));
                        $offset += BLOCKLEN;
                        $offset -= 286;
                        printf ("TEST2: $t_cdr - $offset - $blockhdr - $blockdt\n");
                }

        }

        close(DATA);
        close(OUTPUT);
} else {
        usage();
}