-.diff

diff --git a/mcs/class/System/Test/System.Net.Sockets/SocketTest.cs b/mcs/class/System/Test/System.Net.Sockets/SocketTest.cs
index a7fb500cd3e..a163eb94850 100755
--- a/mcs/class/System/Test/System.Net.Sockets/SocketTest.cs
+++ b/mcs/class/System/Test/System.Net.Sockets/SocketTest.cs
@@ -2879,6 +2879,37 @@ namespace MonoTests.System.Net.Sockets
 			Assert.IsFalse (CWRReceiving);
 		}
 
+		[Test]
+		public void CloseAndOpenWhileReceiving ()
+		{
+			CWRSocket = new Socket (AddressFamily.InterNetwork,
+						SocketType.Dgram,
+						ProtocolType.Udp);
+			CWRSocket.Bind (new IPEndPoint (IPAddress.Loopback,
+							1256));
+
+			Thread recv_thread = new Thread (new ThreadStart (CWRReceiveThread));
+			CWRReady.Reset ();
+			recv_thread.Start ();
+			Thread.Sleep (250);	/* Wait for the thread to be already receiving */
+
+			/* Close the socket and immediately reopen it,
+			 * so that the new one is likely to get the
+			 * same file descriptor as the old one. */
+			CWRSocket.Close ();
+			CWRSocket = new Socket (AddressFamily.InterNetwork,
+						SocketType.Dgram,
+						ProtocolType.Udp);
+			try {
+				if (CWRReady.WaitOne (2000, false) == false) {
+					Assert.Fail ("CloseAndOpenWhileReceiving wait timed out");
+				}
+				Assert.IsFalse (CWRReceiving);
+			} finally {
+				CWRSocket.Close();
+			}
+		}
+
 		static bool RRCLastRead = false;
 		static ManualResetEvent RRCReady = new ManualResetEvent (false);
 		
diff --git a/mono/metadata/w32socket-unix.c b/mono/metadata/w32socket-unix.c
index d675b53e66a..c0e890acd53 100644
--- a/mono/metadata/w32socket-unix.c
+++ b/mono/metadata/w32socket-unix.c
@@ -105,6 +105,8 @@ retry_close:
 			goto retry_close;
 	}
 
+	fprintf (stderr, "0x%lx closed %d\n", pthread_self(), ((MonoFDHandle*) sockethandle)->fd);
+
 	sockethandle->saved_error = 0;
 }
 
@@ -304,6 +306,7 @@ mono_w32socket_recvfrom (SOCKET sock, char *buf, int len, int flags, struct sock
 	SocketHandle *sockethandle;
 	int ret;
 	MonoThreadInfo *info;
+	pthread_t tid = pthread_self ();
 
 	if (!mono_fdhandle_lookup_and_ref(sock, (MonoFDHandle**) &sockethandle)) {
 		mono_w32error_set_last (WSAENOTSOCK);
@@ -319,11 +322,22 @@ mono_w32socket_recvfrom (SOCKET sock, char *buf, int len, int flags, struct sock
 	info = mono_thread_info_current ();
 
 	do {
+		/*
+		 * We're unlucky and the scheduler decides that right
+		 * now something else should run :(
+		 */
+		fprintf (stderr, "0x%lx sleeping on %d...\n", tid, ((MonoFDHandle*) sockethandle)->fd);
+		usleep(500 * 1000);
+
+		fprintf (stderr, "0x%lx receiving on %d...\n", tid, ((MonoFDHandle*) sockethandle)->fd);
+
 		MONO_ENTER_GC_SAFE;
 		ret = recvfrom (((MonoFDHandle*) sockethandle)->fd, buf, len, flags, from, fromlen);
 		MONO_EXIT_GC_SAFE;
 	} while (ret == -1 && errno == EINTR && !mono_thread_info_is_interrupt_state (info));
 
+	fprintf (stderr, "0x%lx received on %d (%d)\n", tid, ((MonoFDHandle*) sockethandle)->fd, ret);
+
 	if (ret == 0 && len > 0) {
 		/* According to the Linux man page, recvfrom only
 		 * returns 0 when the socket has been shut down
@@ -687,6 +701,9 @@ retry_socket:
 	MONO_ENTER_GC_SAFE;
 	fd = socket (domain, type, protocol);
 	MONO_EXIT_GC_SAFE;
+
+	fprintf (stderr, "0x%lx socket %d\n", pthread_self (), fd);
+
 	if (fd == -1) {
 		if (domain == AF_INET && type == SOCK_RAW && protocol == 0) {
 			/* Retry with protocol == 4 (see bug #54565) */