diff --git a/io/CBufferedOutputStream.cpp b/io/CBufferedOutputStream.cpp
index 387ce406..3acd168b 100644
--- a/io/CBufferedOutputStream.cpp
+++ b/io/CBufferedOutputStream.cpp
@@ -13,6 +13,7 @@
 CBufferedOutputStream::CBufferedOutputStream(CMutex* mutex, IJob* closeCB) :
 								m_mutex(mutex),
 								m_closeCB(closeCB),
+								m_empty(mutex, true),
 								m_closed(false)
 {
 	assert(m_mutex != NULL);
@@ -31,6 +32,9 @@ const void*				CBufferedOutputStream::peek(UInt32 n)
 void					CBufferedOutputStream::pop(UInt32 n)
 {
 	m_buffer.pop(n);
+	if (m_buffer.getSize() == 0) {
+		m_empty.broadcast();
+	}
 }
 
 UInt32					CBufferedOutputStream::getSize() const
@@ -67,14 +71,8 @@ UInt32					CBufferedOutputStream::write(
 void					CBufferedOutputStream::flush()
 {
 	// wait until all data is written
-	while (getSizeWithLock() > 0) {
-		CThread::sleep(0.05);
+	CLock lock(m_mutex);
+	while (m_buffer.getSize() > 0) {
+		m_empty.wait();
 	}
 }
-
-UInt32					CBufferedOutputStream::getSizeWithLock() const
-{
-	CLock lock(m_mutex);
-	return m_buffer.getSize();
-}
-
diff --git a/io/CBufferedOutputStream.h b/io/CBufferedOutputStream.h
index 1afbc118..c609336e 100644
--- a/io/CBufferedOutputStream.h
+++ b/io/CBufferedOutputStream.h
@@ -3,6 +3,7 @@
 
 #include "CStreamBuffer.h"
 #include "IOutputStream.h"
+#include "CCondVar.h"
 
 class CMutex;
 class IJob;
@@ -33,12 +34,10 @@ public:
 	virtual UInt32		write(const void*, UInt32 count);
 	virtual void		flush();
 
-private:
-	UInt32				getSizeWithLock() const;
-
 private:
 	CMutex*				m_mutex;
 	IJob*				m_closeCB;
+	CCondVar<bool>		m_empty;
 	CStreamBuffer		m_buffer;
 	bool				m_closed;
 };
diff --git a/net/CTCPSocket.cpp b/net/CTCPSocket.cpp
index 989a9668..3429c9f8 100644
--- a/net/CTCPSocket.cpp
+++ b/net/CTCPSocket.cpp
@@ -80,25 +80,35 @@ void					CTCPSocket::connect(const CNetworkAddress& addr)
 
 void					CTCPSocket::close()
 {
-	// shutdown I/O thread before close
-	if (m_thread != NULL) {
-		// flush if output buffer not empty and output buffer not closed
-		bool doFlush;
-		{
-			CLock lock(m_mutex);
-			doFlush = ((m_connected & kWrite) != 0);
-		}
-		if (doFlush) {
-			m_output->flush();
-		}
+	// see if buffers should be flushed
+	bool doFlush = false;
+	{
+		CLock lock(m_mutex);
+		doFlush = (m_thread != NULL && (m_connected & kWrite) != 0);
+	}
 
-		m_thread->cancel();
+	// flush buffers
+	if (doFlush) {
+		m_output->flush();
+	}
+
+	// cause ioThread to exit
+	{
+		CLock lock(m_mutex);
+		if (m_fd != CNetwork::Null) {
+			CNetwork::shutdown(m_fd, 2);
+			m_connected = kClosed;
+		}
+	}
+
+	// wait for thread
+	if (m_thread != NULL) {
 		m_thread->wait();
 		delete m_thread;
 		m_thread = NULL;
 	}
 
-	CLock lock(m_mutex);
+	// close socket
 	if (m_fd != CNetwork::Null) {
 		if (CNetwork::close(m_fd) == CNetwork::Error) {
 			throw XIOClose();
@@ -190,14 +200,7 @@ void					CTCPSocket::ioService()
 		}
 
 		// check for status
-		CThread::testCancel();
-		if (pfds[0].events == 0) {
-			CThread::sleep(0.05);
-			CThread::testCancel();
-			continue;
-		}
-		const int status = CNetwork::poll(pfds, 1, 50);
-		CThread::testCancel();
+		const int status = CNetwork::poll(pfds, 1, 10);
 
 		// transfer data and handle errors
 		if (status == 1) {