🚀 go-pugleaf

"longshot" <a@ladidadi.nl> wrote in message
news:4272a30c@newsgroups.borland.com...

> I try to send information from one bb app to another using :
>
>  int r = sendto(SOCKET,bytes,length,0,(sockaddr
*)&to,sizeof(sockaddr_in));

How many bytes are you actually sending each time you call sendto()?

> I send 3 packets after eachother.
> The first packet is received corectly, the second one
> is 370 bytes instead of the 20 bytes send.
> The third one isn't received at all.

Did you actually send 370+ bytes to begin with?  If so, then what you
describe is perfectly normal socket behavior.  Multiple packets can (and
usually are) merged together during transmission, and a single packet can
(and usually is) split into multiple transmissions.  Your code has to be
able to handle all three situations (receiving individual packets as-is,
receiving merged packets , and receiving split packets).

> If i place a Sleep(200); between the send calls, i do receive
> the packets correctly.

That just goes to show that your packets are likely being merged together
and your receiving code is not set up to handle that situation.

> Is anyone familliar with this problem and knows a better solution
> than Sleep(200); ???

Re-design your code to handle the packets properly in the first place.  The
best way is to continuously place everything you receive into a buffer, and
then process your packets from the buffer only when they are completely
available.  How you determine when a given packet is completely available
depends on the actual layout of your packets.  Unless all of your packets
are the same fixed length each time, then you have a couple of options:

1) the best thing to do is to place a fixed-length header at the beginning
of each packet which includes a field to specify the size of the remaining
variable-length packet data.  You can then look at the packet header to know
if the remaining packet data is available yet.

2) place a unique delimiter between your packets, using a single byte or a
byte sequence that is guaranteed to never appear inside your packet data.
Then you can look for that delimiter when checking your buffer for complete
packets.


Gambit