在OS X中尝试打开套接字上的写入流时被卡住

在网上阅读了许多示例后，我尝试编写一个简短的简单程序来测试两台计算机之间的套接字连接。我有这两台电脑

• 客户端，192.168.0.116，运行以下程序
• 服务器，192.168.0.118，正在运行http://sockettest.sourceforge.net/在端口6237上处于服务器侦听模式

我一开始采用了更简单的同步设计，但当它不起作用时，我转向了runloop/async。

症状：CFWriteStreamOpen返回true（成功），但流无限期地保持在kCFStreamStatusOpen状态。回调从未被调用以确认打开已完成（事实上，它从未被调用用于任何事件）。

我怀疑我可能有网络问题（防火墙等），可能会阻止此连接。为了反驳这个理论，我跑了http://sockettest.sourceforge.net/客户端上，客户端和服务器连接良好。

#include <iostream>
#include <CoreFoundation/CFStream.h>
using namespace std;
CFStreamClientContext myContext = {0,NULL,NULL,NULL,NULL};
#define SA_HOST "192.168.0.118"
//#define SA_HOST "127.0.0.1"
#define SA_PORT 6237
UInt8 buf[5] = { 0, 1, 2, 3, 4 };
UInt8 *wp = buf;
UInt16 bytesQueued = 5;
UInt16 bytesSent = 0;
static const CFOptionFlags kWriteStreamEvents =
kCFStreamEventEndEncountered |
kCFStreamEventErrorOccurred |
kCFStreamEventCanAcceptBytes |
kCFStreamEventOpenCompleted |
kCFStreamEventNone;
void WriteStreamCB(CFWriteStreamRef writeStream, CFStreamEventType event, void *clientCallBackInfo)
{
    switch (event)
    {
        case kCFStreamEventEndEncountered:
        {
            cout << "in CallBack: kCFStreamEventEndEncounteredd" << endl;
            CFWriteStreamClose(writeStream);
            break;
        }
        case kCFStreamEventErrorOccurred:
        {
            cout << "in CallBack: kCFStreamEventErrorOccurred" << endl;
            CFStreamError err = CFWriteStreamGetError(writeStream);
            cout << "in Callback: stream error, domain: " << err.domain << ", value: " << err.error << endl;
            break;
        }
        case kCFStreamEventCanAcceptBytes:
        {
            cout << "in CallBack: kCFStreamEventCanAcceptBytes" << endl;
            bytesSent = CFWriteStreamWrite(writeStream, buf, 5);
            if (bytesSent > 0)
            {
                bytesQueued -= bytesSent;
                wp += bytesSent;
                cout << "CFWriteStreamWrite wrote " << bytesSent << " bytes, " << bytesQueued << " left" << endl;
            }
            else
            {
                cout << "CFWriteStreamWrite returned " << bytesSent << endl;
            }
            break;
        }
        case kCFStreamEventNone:
        {
            cout << "in CallBack: kCFStreamEventNone" << endl;
            break;
        }
        case kCFStreamEventOpenCompleted:
        {
            cout << "in CallBack: kCFStreamEventNone" << endl;
            break;
        }
    }
}
int main(int argc, const char * argv[]) {
    CFWriteStreamRef   writeStream;
    CFStringRef host = CFSTR(SA_HOST);
    UInt32 port = SA_PORT;
    CFStreamCreatePairWithSocketToHost(kCFAllocatorDefault, host, port, NULL, &writeStream);
    CFWriteStreamSetClient(writeStream, kWriteStreamEvents, WriteStreamCB, &myContext);
    CFWriteStreamScheduleWithRunLoop(writeStream, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode);
    if (!CFWriteStreamOpen(writeStream))
    {
        return -1;
    }
    while (true);
    return 0;
}