ioctlsocket(...) don't work properly.

[sulacco]

Does anybody know why ioctlsocket don't work properly.
It must place how much bytes is waiting in socket.
When I place breakpoint to ioctlsocket then this function place how much
bytes is waiting in i_HowMuch. But if I remove breakpoint then in
i_HowMuch just zero. Why that? What's the problem.
I'm using ioctlsocket(...) to know beforehand how much bytes are waiting
me so I can create dynamic buffer.


if(send(ServerSock, Retro, strlen(Retro), 0)==SOCKET_ERROR){

i_ErrorSock=WSAGetLastError();
return false;
}
//memset(sBuf,0,sizeof(sBuf));
if(ioctlsocket(ServerSock,FIONREAD,&i_HowMuch)==SOCKET_ERROR){

i_ErrorSock=WSAGetLastError();
return false;
}

 

[Salem]

> But if I remove breakpoint then in
> i_HowMuch just zero. Why that? What's the problem.
You're not waiting long enough for an answer to come back

> if(send(ServerSock, Retro, strlen(Retro), 0)==SOCKET_ERROR){
Send some data off to some remote location (this will take time - lots of time in comparison to the speed at which code executes at).

You've broken http://java.sun.com/people/jag/Fallacies.html]Rule Number 2[/url]

> if(ioctlsocket(ServerSock,FIONREAD,&i_HowMuch)==SOCKET_ERROR){
Determine how much information has been received so far.
With a breakpoint, you give the remote a nice long time (many seconds) to reply and hence you get the answer you expect. Charging through at light-speed without a breakpoint gives the remote no chance whatsoever to respond.

You need to wait in a loop (or go do other things as well) for the reply to come back. You also need to be prepared for the reply never coming back.

--

 

[sulacco]

Thanks. I used Sleep(...) but i've got gut feeling this isn't professional.

 

[sulacco]

What about this one:

u_long i_HowMuch=0;

while(!i_HowMuch){
if(ioctlsocket(ServerSock,FIONREAD,&i_HowMuch)==SOCKET_ERROR){
i_ErrorSock=WSAGetLastError();
return false;
}
}
will be it enough? But then again what if the loop will be infinite?

 

[Salem]

Please use TGML [tt][ignore]

[/ignore][/tt] tags when posting code.

Yes, the loop could be infinite
So add a timeout

u_long i_HowMuch=0;
u_long i_Timeout=0;

while(!i_HowMuch && i_Timeout < 10 ){
    if(ioctlsocket(ServerSock,FIONREAD,&i_HowMuch)==SOCKET_ERROR){
        i_ErrorSock=WSAGetLastError();
        return false;
    }
    Sleep( 1000 );  // sleep for a second
    i_Timeout++;    // bump the count
}
if ( i_Timeout == 10 ) {
    // set some other error condition
    return false;
}

--

 

[sulacco]

Thanks, Salem.
checking code tags...
<code>index++;</code>

 

[sulacco]

check again...

index++