Re: Socket differences between localhost and LAN (or Internet)

From:

"William DePalo [MVP VC++]" <willd.no.spam@mvps.org>

Newsgroups:

microsoft.public.vc.ide_general

Date:

Fri, 8 Sep 2006 12:57:27 -0400

Message-ID:

<e9Qaef20GHA.4228@TK2MSFTNGP06.phx.gbl>

"Wyvern" <davinator17@hotmail.com> wrote in message
news:1157728119.299200.177660@b28g2000cwb.googlegroups.com...

But why ? It's TCP, I expect that if I send 1024 bytes, I receive 1024
bytes; if what I send is not what I receive it is a very big trouble, I
don't understand. WHy in a network those values are different ? WHat
can I do ? What if I try to "reask" for the missing data but the
dimension of missing data doesn't come correctly to the server ? In
this case it would be a complete tragedy...

I see that Scott has already pointed you to a tutorial. I'll just repeat
what I said, upfront.

If you are sending variably sized messages, it would be a good idea to use a
fixed header in which one of its members contains the length of the message
to follow. Once you know the length, you just keep calling recv() until you
have the whole message.

I didn't mention an alternate technique which would have you use a special
marker to signal the end of transmission. That's only an option if you know
for sure that there is a byte or set of bytes which can not occur in the
data that you send.

Regards,
Will