13 Mar
2006
13 Mar
'06
7:34 p.m.
On Tue, 2006-03-14 at 00:21 +0100, fons adriaensen wrote:
On Mon, Mar 13, 2006 at 11:59:15PM +0100, stefan
kersten wrote:
i don't believe that "network order" is defined for floats, but one
could reasonably assume it was the same big-endian ordering. however,
since the IEEE spec crosses 8 bit boundaries (IIRC), simply using *to*
isn't going to work. i think this applies also to doubles.
ntohf and htonf would be required, i think.
as paul stated, network byte order is defined to
be
big-endian, so yes, you have to convert 32 bit floats (and
doubles, for that matter) on intel, because they are stored
lsb first. of course it would be perfectly valid for netjack
to use little endian `on the wire'; but this would be like
putting my powerbook in little endian mode when playing a
wav file. sort of.
OK, but for floats the situation could be more complex. On Intel,
the exponent/sign byte is the last one. Is it always the first
one on BE platforms ? If it isn't then using ntohl() or htonl()
wich are designed to work on 32-bit ints will not help.
For doubles, things are even more fuzzy. Can you just use ntohl()
and htonl() on both halves, or do these two have to be swapped as
well ? Will either rule produce consistent results on all
platforms ?