Using CDPipeListen Asynchronously in Windows Applications

One of the Newton 2.x OS Q&As
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This document was exported on 7/23/97.

Using CDPipeListen Asynchronously in Windows Applications (7/15/96)

Q: I am passing in a callback function to CDPipeListen, but it never seems to be called. What is going wrong?

A: Due to a bug in CDPipeListen, the callback function never gets called in Windows applications. You will have to use a synchronous listen, then wait for the state of the DIL pipe to change before accepting the connection. The following code shows how to properly accept a connection.
anErr = CDPipeListen( gOurPipe, kDefaultTimeout, NULL, 0 );

if (!anErr) 
{
    // This code doesn't need to be executed on MacOS, but 
    // is currently required for Windows.  We need to loop,
    // waiting for the connection state to change to
    // kCDIL_ConnectPending.
    endTime = (GetTickCount()/1000) + 30;  // to timeout in 30 seconds
    while ((GetTickCount()/1000) < endTime ) 
    {
        if (CDGetPipeState( gOurPipe ) == kCDIL_ConnectPending) {
            anErr = CDPipeAccept( gOurPipe );
            break;
        } else
            CDIdle( gOurPipe );
    }
}


Note: this has been fixed in the Windows DILs 1.0.2.