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pipes

Did you used pipes? How can I wait for a connection at the server end of the pipe (for a blocking pipe), without using ConnectNamedPipe() (that is a blocking function)? MSDN says that ConnectNamedPipe() only role is to wait for client connexion. I tried to replace this function with a while loop, but the client didn't connect:

while( LINK_OK != m_pCommServer->m_iLinkStatus )
{
TRACE("HProtocolPipeServer::Wait() ~~~ Waiting client to connect\n");
GetNamedPipeHandleState (m_hPipe,&dwInstances,NULL,NULL,NULL,NULL,0);
if(1>dwInstances)
{
::Sleep(100);
continue;
}
}

Thanx,
H

oldbaby

ConnectNamedPipe() API is equivalent of tcp/ip accept()
(CreateNamedPipe() then maps to listen(...,backlog) where
backlog in your case is max number of pipe instances).
I hope this tcp/ip metaphore would help you understand
the mechanics of named pipe protocol.
To enable non-blocking mode (if your consern is about blocking while waiting for a client ) you woild have to use overlapped i/o e.g:
//server dedicated thread function
...
//connection event
OVERLAPPED ov;
ZeroMemory(&ov,sizeof(ov));
//manually set event
ov.hEvent = CreateEvent(NULL,TRUE,...);
//start waiting for clients
for(;;){
TRACE("HProtocolPipeServer::Wait() ~~~ Waiting client to connect\n");
DWORD dwRet = WaitForSingleObject(ov.hEvent,INFINITE);
TRACE("HProtocolPipeServer::Wait() connected!\n");
if(WAIT_FALED == dwRet)
continue;
ResetEvent(ov.hEvent);
//do some processing ,be as short as possible
}

Here I tried to replicate semantics of your code:)

Stanciu

ASKER

I resolve this problem building some client pipes on server application, connecting these pipes to server pipes, and then closing'em all.

Thanx anyway,

H

ASKER CERTIFIED SOLUTION

Netminder

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