Re: sockets: htonl question

From:
mlimber <mlimber@gmail.com>
Newsgroups:
comp.lang.c++
Date:
Wed, 23 Jul 2008 09:23:55 -0700 (PDT)
Message-ID:
<b0fb261b-857b-4ed9-b443-942d9da74677@m36g2000hse.googlegroups.com>
On Jul 23, 12:16 pm, Tom Impelluso <impel...@attila.sdsu.edu> wrote:

Hello,

I am aware of the need for ntohl and htonl.
But floats?

I am aware of Beej's (Brian "Beej Jorgensen" Hall) implementation:http://=

beej.us/guide/bgnet/output/html/singlepage/bgnet.html#htonsman

Yet, I devised my own kludge:
------------------------
uint32_t data, data1;
float num1;

i =read(descriptor, (char *) &data, sizeof(uint32_t));
data1 = ntohl(data);
num1 = *(float*) ( &data1);
--------------------------

This works for me; always has!
Now, mind you, I have done scientific coding.
And in an enviroment with extremley well-behaved floats,
where round-off has never been an issue.
And very little exceptions....

So...

Why does my simpler implementation work?
What problems could it cause?
Friends have advised me to use Jorgensen, but I do not see the need.
(I also have not gotten it to work)


Sockets are technically off-topic here (cf. <http://www.parashift.com/c
++-faq-lite/how-to-post.html#faq-5.9>).

<OT>I think "Beej" addresses your question as to why in section 6.4
<http://beej.us/guide/bgnet/output/html/singlepage/
bgnet.html#serialization> when he mentions different binary formats
for floating point numbers.</OT>

Cheers! --M

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