diff --git a/luprex/core/cpp/driver-common.cpp b/luprex/core/cpp/driver-common.cpp
index 801ce63e..4ca10a19 100644
--- a/luprex/core/cpp/driver-common.cpp
+++ b/luprex/core/cpp/driver-common.cpp
@@ -380,12 +380,14 @@ public:
             struct pollfd &pfd = pollvec[index++];
             pfd.fd = p.second;
             pfd.events = POLLIN;
+            pfd.revents = 0;
         }
         for (const ChanInfo &chan : chans_) {
             struct pollfd &pfd = pollvec[index++];
             assert(chan.socket != INVALID_SOCKET);
             pfd.fd = chan.socket;
-            pfd.events = POLLERR;
+            pfd.events = 0;
+            pfd.revents = 0;
             if (chan.ready_now) mstimeout = 0;
             if (chan.just_released) mstimeout = 0;
             if (chan.ready_on_pollin) pfd.events |= POLLIN;
@@ -413,7 +415,7 @@ public:
             struct pollfd &pfd = pollvec[index++];
             bool pollin = ((pfd.revents & POLLIN) != 0);
             bool pollout = ((pfd.revents & POLLOUT) != 0);
-            bool pollerr = ((pfd.revents & POLLERR) != 0);
+            bool pollerr = ((pfd.revents & (POLLERR | POLLHUP)) != 0);
             if (chan.ready_now || pollerr || chan.just_released ||
                 (chan.ready_on_pollin && pollin) ||
                 (chan.ready_on_pollout && pollout) ||
@@ -433,6 +435,7 @@ public:
     }
 
     void drive(DrivenEngine *de, int argc, char *argv[]) {
+        socket_init();
         SSL_load_error_strings();
         ERR_load_crypto_strings();
         enable_tty_raw();
@@ -476,6 +479,7 @@ public:
         SSL_CTX_free(ssl_ctx_with_root_certs_);
         SSL_CTX_free(ssl_ctx_with_server_certs_);
         DrivenEngine::set(nullptr);
+        socket_uninit();
     }
 };
 
diff --git a/luprex/core/cpp/driver-mingw.cpp b/luprex/core/cpp/driver-mingw.cpp
index c39a62e0..ff4ca8c5 100644
--- a/luprex/core/cpp/driver-mingw.cpp
+++ b/luprex/core/cpp/driver-mingw.cpp
@@ -35,6 +35,12 @@ static void enable_tty_raw() {
     // Do nothing on windows.
 }
 
+static std::string winsock_error_string(int errcode) {
+    std::ostringstream oss;
+    oss << "error " << errcode;
+    return oss.str();
+}
+
 static PADDRINFOA find_good_addr(PADDRINFOA addrinfo) {
     for (PADDRINFOA addr = addrinfo; addr != nullptr; addr = addr->ai_next) {
         if (addr->ai_family == AF_INET) {
@@ -117,6 +123,7 @@ SOCKET listen_on_port(int port, std::string &err) {
         goto error;
     }
     set_nonblocking(sock);
+    std::cerr << "listening socket is " << sock << std::endl;
     return sock;
 
 error:
@@ -128,6 +135,7 @@ static SOCKET accept_on_socket(SOCKET listen_socket, std::string &err) {
     SOCKET chsock = accept(listen_socket, nullptr, nullptr);
     if (chsock != INVALID_SOCKET) {
         set_nonblocking(chsock);
+        std::cerr << "accepted socket is " << chsock << std::endl;
         return chsock;
     } else {
         int errcode = WSAGetLastError();
@@ -182,13 +190,25 @@ static int socket_close(SOCKET socket) {
 static int socket_poll(PollVector &pollvec, int mstimeout, std::string &err) {
     int status = WSAPoll(&pollvec[0], pollvec.size(), mstimeout);
     if (status < 0) {
-        WSAGetLastError();
-        err = "poll failed";
+        err = winsock_error_string(WSAGetLastError());
         return -1;
     }
     return status;
 }
 
+static void socket_init() {
+    WSADATA data;
+    int errcode = WSAStartup(2, &data);
+    if (errcode != 0) {
+        fprintf(stderr, "Winsock didn't initalize, error %d", errcode);
+        exit(1);
+    }
+}
+
+static void socket_uninit() {
+    // Nothing needed.
+}
+
 static int console_write(const char *bytes, int nbytes) {
     if (nbytes == 0) return 0;
     HANDLE hstdout = GetStdHandle(STD_OUTPUT_HANDLE);