WORKS!>	@q     =unpack("Q*", $buf);  $sq  = scalar(@q)  ||  -1;
FAIL!	@uint48=unpack("S3", $buf);  $s48 = scalar(@uint48)  ||  -1;
FAIL!	@uint48=unpack("S@3", $buf);  $s48 = scalar(@uint48)  ||  -1;
FAIL!	@uint48=unpack("S[3]", $buf);  $s48 = scalar(@uint48)  ||  -1;
FAIL!	@uint48=unpack("(SSS)*", $buf);  $s48 = scalar(@uint48)  ||  -1;