diff --git a/READMEs/README.coding.md b/READMEs/README.coding.md
index a6f8e231..218b4454 100644
--- a/READMEs/README.coding.md
+++ b/READMEs/README.coding.md
@@ -132,7 +132,7 @@ with the socket closing and the `wsi` freed.
 Websocket write activities should only take place in the
 `LWS_CALLBACK_SERVER_WRITEABLE` callback as described below.
 
-[This network-programming necessity to link the issue of new data to
+This network-programming necessity to link the issue of new data to
 the peer taking the previous data is not obvious to all users so let's
 repeat that in other words:
 
@@ -155,12 +155,20 @@ websocket ones, you can combine them together with the websocket ones
 in one poll loop, see "External Polling Loop support" below, and
 still do it all in one thread / process context.
 
-If you insist on trying to use it from multiple threads, take special care if
-you might simultaneously create more than one context from different threads.
-
 SSL_library_init() is called from the context create api and it also is not
 reentrant.  So at least create the contexts sequentially.
 
+If you must interoperate with other threads, you can use `lws_cancel_service()`
+to notify lws that something has happened on another thread.  lws will send
+`LWS_CALLBACK_EVENT_WAIT_CANCELLED` events to all protocols, serialized with
+the main event loop operations, ie, safely.
+
+You can handle this callback to check the reason you were notified and take
+action using any usual lws api, since you are in a callback in the normal
+service thread.
+
+`lws_cancel_service()` is very cheap for the other thread to call.
+
 @section closing Closing connections from the user side
 
 When you want to close a connection, you do it by returning `-1` from a
diff --git a/lib/context.c b/lib/context.c
index d68f3f42..0462bd64 100644
--- a/lib/context.c
+++ b/lib/context.c
@@ -834,6 +834,77 @@ lws_init_vhost_client_ssl(const struct lws_context_creation_info *info,
 	return lws_context_init_client_ssl(&i, vhost);
 }
 
+LWS_VISIBLE void
+lws_cancel_service_pt(struct lws *wsi)
+{
+	lws_plat_pipe_signal(wsi);
+}
+
+LWS_VISIBLE void
+lws_cancel_service(struct lws_context *context)
+{
+	struct lws_context_per_thread *pt = &context->pt[0];
+	short m = context->count_threads;
+
+	lwsl_notice("%s\n", __func__);
+
+	while (m--) {
+		if (pt->pipe_wsi)
+			lws_plat_pipe_signal(pt->pipe_wsi);
+		pt++;
+	}
+}
+
+int
+lws_create_event_pipes(struct lws_context *context)
+{
+	struct lws *wsi;
+	int n;
+
+	/*
+	 * Create the pt event pipes... these are unique in that they are
+	 * not bound to a vhost or protocol (both are NULL)
+	 */
+
+	for (n = 0; n < context->count_threads; n++) {
+		if (context->pt[n].pipe_wsi)
+			continue;
+
+		wsi = lws_zalloc(sizeof(*wsi), "event pipe wsi");
+		if (!wsi) {
+			lwsl_err("Out of mem\n");
+			return 1;
+		}
+		wsi->context = context;
+		wsi->mode = LWSCM_EVENT_PIPE;
+		wsi->protocol = NULL;
+		wsi->tsi = n;
+		wsi->vhost = NULL;
+		wsi->event_pipe = 1;
+
+		if (lws_plat_pipe_create(wsi)) {
+			lws_free(wsi);
+			continue;
+		}
+		wsi->desc.sockfd = context->pt[n].dummy_pipe_fds[0];
+		lwsl_debug("event pipe fd %d\n", wsi->desc.sockfd);
+
+		context->pt[n].pipe_wsi = wsi;
+
+		lws_libuv_accept(wsi, wsi->desc);
+		lws_libev_accept(wsi, wsi->desc);
+		lws_libevent_accept(wsi, wsi->desc);
+
+		if (insert_wsi_socket_into_fds(context, wsi))
+			return 1;
+
+		lws_change_pollfd(context->pt[n].pipe_wsi, 0, LWS_POLLIN);
+		context->count_wsi_allocated++;
+	}
+
+	return 0;
+}
+
 LWS_VISIBLE struct lws_context *
 lws_create_context(struct lws_context_creation_info *info)
 {
@@ -1156,6 +1227,16 @@ lws_create_context(struct lws_context_creation_info *info)
 	context->count_caps = info->count_caps;
 #endif
 
+	/*
+	 * The event libs handle doing this when their event loop starts,
+	 * if we are using the default poll() service, do it here
+	 */
+
+	if (!LWS_LIBEV_ENABLED(context) &&
+	    !LWS_LIBUV_ENABLED(context) &&
+	    !LWS_LIBEVENT_ENABLED(context) && lws_create_event_pipes(context))
+		goto bail;
+
 	/*
 	 * drop any root privs for this process
 	 * to listen on port < 1023 we would have needed root, but now we are
@@ -1515,9 +1596,15 @@ lws_context_destroy(struct lws_context *context)
 			if (!wsi)
 				continue;
 
-			lws_close_free_wsi(wsi,
-				LWS_CLOSE_STATUS_NOSTATUS_CONTEXT_DESTROY
-				/* no protocol close */);
+			if (wsi->event_pipe) {
+				lws_plat_pipe_close(wsi);
+				remove_wsi_socket_from_fds(wsi);
+				lws_free(wsi);
+				context->count_wsi_allocated--;
+			} else
+				lws_close_free_wsi(wsi,
+					LWS_CLOSE_STATUS_NOSTATUS_CONTEXT_DESTROY
+					/* no protocol close */);
 			n--;
 		}
 		lws_pt_mutex_destroy(pt);
diff --git a/lib/event-libs/libev.c b/lib/event-libs/libev.c
index 2410488f..9a9d6e06 100644
--- a/lib/event-libs/libev.c
+++ b/lib/event-libs/libev.c
@@ -92,6 +92,9 @@ lws_ev_initloop(struct lws_context *context, struct ev_loop *loop, int tsi)
 
 	context->pt[tsi].io_loop_ev = loop;
 
+	if (lws_create_event_pipes(context))
+		return -1;
+
 	/*
 	 * Initialize the accept w_accept with all the listening sockets
 	 * and register a callback for read operations
diff --git a/lib/event-libs/libevent.c b/lib/event-libs/libevent.c
index 08b5a8d3..ad12ac51 100644
--- a/lib/event-libs/libevent.c
+++ b/lib/event-libs/libevent.c
@@ -98,6 +98,9 @@ int tsi)
 		context->pt[tsi].io_loop_event_base = loop;
 	}
 
+	if (lws_create_event_pipes(context))
+		return 1;
+
 	/*
 	* Initialize all events with the listening sockets
 	* and register a callback for read operations
diff --git a/lib/event-libs/libuv.c b/lib/event-libs/libuv.c
index 60c93390..e88f1cff 100644
--- a/lib/event-libs/libuv.c
+++ b/lib/event-libs/libuv.c
@@ -227,6 +227,9 @@ lws_uv_initloop(struct lws_context *context, uv_loop_t *loop, int tsi)
 	} else
 		first = 0;
 
+	if (lws_create_event_pipes(context))
+		goto bail;
+
 	/*
 	 * Initialize the accept wsi read watcher with all the listening sockets
 	 * and register a callback for read operations
@@ -247,6 +250,9 @@ lws_uv_initloop(struct lws_context *context, uv_loop_t *loop, int tsi)
 	}
 
 	return status;
+
+bail:
+	return -1;
 }
 
 static void lws_uv_close_cb(uv_handle_t *handle)
@@ -325,7 +331,7 @@ lws_libuv_accept(struct lws *wsi, lws_sock_file_fd_type desc)
 		return;
 
 	wsi->w_read.context = context;
-	if (wsi->mode == LWSCM_RAW_FILEDESC)
+	if (wsi->mode == LWSCM_RAW_FILEDESC || wsi->event_pipe)
 		uv_poll_init(pt->io_loop_uv, &wsi->w_read.uv_watcher,
 			     (int)desc.filefd);
 	else
diff --git a/lib/libwebsockets.c b/lib/libwebsockets.c
index c371ad95..91bf5173 100644
--- a/lib/libwebsockets.c
+++ b/lib/libwebsockets.c
@@ -85,7 +85,7 @@ lws_free_wsi(struct lws *wsi)
 	lws_header_table_force_to_detachable_state(wsi);
 	lws_header_table_detach(wsi, 0);
 
-	if (wsi->vhost->lserv_wsi == wsi)
+	if (wsi->vhost && wsi->vhost->lserv_wsi == wsi)
 		wsi->vhost->lserv_wsi = NULL;
 
 	lws_pt_lock(pt);
@@ -822,8 +822,9 @@ lws_close_free_wsi_final(struct lws *wsi)
 	}
 
 	/* outermost destroy notification for wsi (user_space still intact) */
-	wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_WSI_DESTROY,
-				          wsi->user_space, NULL, 0);
+	if (wsi->vhost)
+		wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_WSI_DESTROY,
+						  wsi->user_space, NULL, 0);
 
 #ifdef LWS_WITH_CGI
 	if (wsi->cgi) {
diff --git a/lib/libwebsockets.h b/lib/libwebsockets.h
index 6721aa26..9c756d30 100644
--- a/lib/libwebsockets.h
+++ b/lib/libwebsockets.h
@@ -1416,6 +1416,12 @@ enum lws_callback_reasons {
 	LWS_CALLBACK_CGI_PROCESS_ATTACH				= 70,
 	/**< CGI: Sent when the CGI process is spawned for the wsi.  The
 	 * len parameter is the PID of the child process */
+	LWS_CALLBACK_EVENT_WAIT_CANCELLED			= 71,
+	/**< This is sent to every protocol of every vhost in response
+	 * to lws_cancel_service() or lws_cancel_service_pt().  This
+	 * callback is serialized in the lws event loop normally, even
+	 * if the lws_cancel_service[_pt]() call was from a different
+	 * thread. */
 
 	/****** add new things just above ---^ ******/
 
@@ -3440,15 +3446,8 @@ lws_service_tsi(struct lws_context *context, int timeout_ms, int tsi);
  *				on one thread
  * \param wsi:	Cancel service on the thread this wsi is serviced by
  *
- *	This function lets a call to lws_service() waiting for a timeout
- *	immediately return.
- *
- *	It works by creating a phony event and then swallowing it silently.
- *
- *	The reason it may be needed is when waiting in poll(), changes to
- *	the event masks are ignored by the OS until poll() is reentered.  This
- *	lets you halt the poll() wait and make the reentry happen immediately
- *	instead of having the wait out the rest of the poll timeout.
+ * Same as lws_cancel_service(), but targets a single service thread, the one
+ * the wsi belongs to.  You probably want to use lws_cancel_service() instead.
  */
 LWS_VISIBLE LWS_EXTERN void
 lws_cancel_service_pt(struct lws *wsi);
@@ -3457,12 +3456,13 @@ lws_cancel_service_pt(struct lws *wsi);
  * lws_cancel_service() - Cancel wait for new pending socket activity
  * \param context:	Websocket context
  *
- *	This function let a call to lws_service() waiting for a timeout
- *	immediately return.
+ * This function creates an immediate "synchronous interrupt" to the lws poll()
+ * wait or event loop.  As soon as possible in the serialzed service sequencing,
+ * a LWS_CALLBACK_EVENT_WAIT_CANCELLED callback is sent to every protocol on
+ * every vhost.
  *
- *	What it basically does is provide a fake event that will be swallowed,
- *	so the wait in poll() is ended.  That's useful because poll() doesn't
- *	attend to changes in POLLIN/OUT/ERR until it re-enters the wait.
+ * lws_cancel_service() may be called from another thread while the context
+ * exists, and its effect will be immediately serialized.
  */
 LWS_VISIBLE LWS_EXTERN void
 lws_cancel_service(struct lws_context *context);
diff --git a/lib/plat/lws-plat-esp32.c b/lib/plat/lws-plat-esp32.c
index 58b5281f..88ab7682 100644
--- a/lib/plat/lws-plat-esp32.c
+++ b/lib/plat/lws-plat-esp32.c
@@ -317,6 +317,24 @@ lws_plat_drop_app_privileges(struct lws_context_creation_info *info)
 {
 }
 
+
+int
+lws_plat_pipe_create(struct lws *wsi)
+{
+	return 1;
+}
+
+int
+lws_plat_pipe_signal(struct lws *wsi)
+{
+	return 1;
+}
+
+void
+lws_plat_pipe_close(struct lws *wsi)
+{
+}
+
 LWS_VISIBLE int
 lws_plat_context_early_init(void)
 {
diff --git a/lib/plat/lws-plat-esp8266.c b/lib/plat/lws-plat-esp8266.c
index 90ddbdf3..60623e3d 100644
--- a/lib/plat/lws-plat-esp8266.c
+++ b/lib/plat/lws-plat-esp8266.c
@@ -41,6 +41,24 @@ time_t time(time_t *tloc)
 	return 0;
 }
 
+
+int
+lws_plat_pipe_create(struct lws *wsi)
+{
+	return 1;
+}
+
+int
+lws_plat_pipe_signal(struct lws *wsi)
+{
+	return 1;
+}
+
+void
+lws_plat_pipe_close(struct lws *wsi)
+{
+}
+
 LWS_VISIBLE int
 lws_get_random(struct lws_context *context, void *buf, int len)
 {
@@ -171,16 +189,6 @@ lws_poll_listen_fd(struct lws_pollfd *fd)
 	return 0;
 }
 
-LWS_VISIBLE void
-lws_cancel_service_pt(struct lws *wsi)
-{
-}
-
-LWS_VISIBLE void
-lws_cancel_service(struct lws_context *context)
-{
-}
-
 LWS_VISIBLE void lwsl_emit_syslog(int level, const char *line)
 {
 	extern void output_redirect(const char *str);
diff --git a/lib/plat/lws-plat-optee.c b/lib/plat/lws-plat-optee.c
index 55677af6..4863ba05 100644
--- a/lib/plat/lws-plat-optee.c
+++ b/lib/plat/lws-plat-optee.c
@@ -4,6 +4,23 @@
  * included from libwebsockets.c for OPTEE builds
  */
 
+int
+lws_plat_pipe_create(struct lws *wsi)
+{
+	return 1;
+}
+
+int
+lws_plat_pipe_signal(struct lws *wsi)
+{
+	return 1;
+}
+
+void
+lws_plat_pipe_close(struct lws *wsi)
+{
+}
+
 void TEE_GenerateRandom(void *randomBuffer, uint32_t randomBufferLen);
 
 unsigned long long time_in_microseconds(void)
@@ -52,32 +69,6 @@ lws_poll_listen_fd(struct lws_pollfd *fd)
 	return 0;
 }
 
-LWS_VISIBLE void
-lws_cancel_service_pt(struct lws *wsi)
-{
-#if 0
-	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
-	char buf = 0;
-
-	if (write(pt->dummy_pipe_fds[1], &buf, sizeof(buf)) != 1)
-		lwsl_err("Cannot write to dummy pipe");
-#endif
-}
-
-LWS_VISIBLE void
-lws_cancel_service(struct lws_context *context)
-{
-#if 0
-	struct lws_context_per_thread *pt = &context->pt[0];
-	char buf = 0, m = context->count_threads;
-
-	while (m--) {
-		if (write(pt->dummy_pipe_fds[1], &buf, sizeof(buf)) != 1)
-			lwsl_err("Cannot write to dummy pipe");
-		pt++;
-	}
-#endif
-}
 #if 0
 LWS_VISIBLE void lwsl_emit_syslog(int level, const char *line)
 {
diff --git a/lib/plat/lws-plat-unix.c b/lib/plat/lws-plat-unix.c
index 068222bb..6e824a34 100644
--- a/lib/plat/lws-plat-unix.c
+++ b/lib/plat/lws-plat-unix.c
@@ -29,6 +29,41 @@
 #endif
 #include <dirent.h>
 
+int
+lws_plat_pipe_create(struct lws *wsi)
+{
+	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
+
+	return pipe(pt->dummy_pipe_fds);
+}
+
+int
+lws_plat_pipe_signal(struct lws *wsi)
+{
+	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
+	char buf = 0;
+	int n;
+
+	n = write(pt->dummy_pipe_fds[1], &buf, 1);
+
+	lwsl_debug("%s: fd %d %d\n", __func__, pt->dummy_pipe_fds[1], n);
+
+	return n != 1;
+}
+
+void
+lws_plat_pipe_close(struct lws *wsi)
+{
+	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
+
+	if (pt->dummy_pipe_fds[0] && pt->dummy_pipe_fds[0] != -1)
+		close(pt->dummy_pipe_fds[0]);
+	if (pt->dummy_pipe_fds[1] && pt->dummy_pipe_fds[1] != -1)
+		close(pt->dummy_pipe_fds[1]);
+
+	pt->dummy_pipe_fds[0] = pt->dummy_pipe_fds[1] = -1;
+}
+
 unsigned long long time_in_microseconds(void)
 {
 	struct timeval tv;
@@ -77,29 +112,6 @@ lws_poll_listen_fd(struct lws_pollfd *fd)
 	return poll(fd, 1, 0);
 }
 
-LWS_VISIBLE void
-lws_cancel_service_pt(struct lws *wsi)
-{
-	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
-	char buf = 0;
-
-	if (write(pt->dummy_pipe_fds[1], &buf, sizeof(buf)) != 1)
-		lwsl_err("Cannot write to dummy pipe");
-}
-
-LWS_VISIBLE void
-lws_cancel_service(struct lws_context *context)
-{
-	struct lws_context_per_thread *pt = &context->pt[0];
-	char buf = 0, m = context->count_threads;
-
-	while (m--) {
-		if (write(pt->dummy_pipe_fds[1], &buf, sizeof(buf)) != 1)
-			lwsl_err("Cannot write to dummy pipe");
-		pt++;
-	}
-}
-
 LWS_VISIBLE void lwsl_emit_syslog(int level, const char *line)
 {
 	int syslog_level = LOG_DEBUG;
@@ -126,7 +138,6 @@ _lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 {
 	struct lws_context_per_thread *pt;
 	int n = -1, m, c;
-	char buf;
 
 	/* stay dead once we are dead */
 
@@ -200,12 +211,6 @@ faked_service:
 
 		c--;
 
-		if (pt->fds[n].fd == pt->dummy_pipe_fds[0]) {
-			if (read(pt->fds[n].fd, &buf, 1) != 1)
-				lwsl_err("Cannot read from dummy pipe.");
-			continue;
-		}
-
 		m = lws_service_fd_tsi(context, &pt->fds[n], tsi);
 		if (m < 0)
 			return -1;
@@ -543,9 +548,6 @@ lws_plat_context_early_destroy(struct lws_context *context)
 LWS_VISIBLE void
 lws_plat_context_late_destroy(struct lws_context *context)
 {
-	struct lws_context_per_thread *pt = &context->pt[0];
-	int m = context->count_threads;
-
 #ifdef LWS_WITH_PLUGINS
 	if (context->plugin_list)
 		lws_plat_plugins_destroy(context);
@@ -554,13 +556,6 @@ lws_plat_context_late_destroy(struct lws_context *context)
 	if (context->lws_lookup)
 		lws_free(context->lws_lookup);
 
-	while (m--) {
-		if (pt->dummy_pipe_fds[0])
-			close(pt->dummy_pipe_fds[0]);
-		if (pt->dummy_pipe_fds[1])
-			close(pt->dummy_pipe_fds[1]);
-		pt++;
-	}
 	if (!context->fd_random)
 		lwsl_err("ZERO RANDOM FD\n");
 	if (context->fd_random != LWS_INVALID_FILE)
@@ -794,13 +789,11 @@ _lws_plat_file_write(lws_fop_fd_t fop_fd, lws_filepos_t *amount,
 	return 0;
 }
 
-
 LWS_VISIBLE int
 lws_plat_init(struct lws_context *context,
 	      struct lws_context_creation_info *info)
 {
-	struct lws_context_per_thread *pt = &context->pt[0];
-	int n = context->count_threads, fd;
+	int fd;
 
 	/* master context has the global fd lookup array */
 	context->lws_lookup = lws_zalloc(sizeof(struct lws *) *
@@ -822,25 +815,9 @@ lws_plat_init(struct lws_context *context,
 		return 1;
 	}
 
-	if (!lws_libev_init_fd_table(context) &&
-	    !lws_libuv_init_fd_table(context) &&
-	    !lws_libevent_init_fd_table(context)) {
-		/* otherwise libev/uv/event handled it instead */
-
-		while (n--) {
-			if (pipe(pt->dummy_pipe_fds)) {
-				lwsl_err("Unable to create pipe\n");
-				return 1;
-			}
-
-			/* use the read end of pipe as first item */
-			pt->fds[0].fd = pt->dummy_pipe_fds[0];
-			pt->fds[0].events = LWS_POLLIN;
-			pt->fds[0].revents = 0;
-			pt->fds_count = 1;
-			pt++;
-		}
-	}
+	(void)lws_libev_init_fd_table(context);
+	(void)lws_libuv_init_fd_table(context);
+	(void)lws_libevent_init_fd_table(context);
 
 #ifdef LWS_WITH_PLUGINS
 	if (info->plugin_dirs)
diff --git a/lib/plat/lws-plat-win.c b/lib/plat/lws-plat-win.c
index f5b178ce..8f1ecf75 100644
--- a/lib/plat/lws-plat-win.c
+++ b/lib/plat/lws-plat-win.c
@@ -3,6 +3,27 @@
 #endif
 #include "private-libwebsockets.h"
 
+int
+lws_plat_pipe_create(struct lws *wsi)
+{
+	return 1;
+}
+
+int
+lws_plat_pipe_signal(struct lws *wsi)
+{
+	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
+
+	WSASetEvent(pt->events[0]);
+
+	return 0;
+}
+
+void
+lws_plat_pipe_close(struct lws *wsi)
+{
+}
+
 unsigned long long
 time_in_microseconds()
 {
@@ -81,7 +102,7 @@ delete_from_fd(struct lws_context *context, lws_sockfd_type fd)
 		if (context->fd_hashtable[h].wsi[n]->desc.sockfd == fd) {
 			while (n < context->fd_hashtable[h].length) {
 				context->fd_hashtable[h].wsi[n] =
-						context->fd_hashtable[h].wsi[n + 1];
+					context->fd_hashtable[h].wsi[n + 1];
 				n++;
 			}
 			context->fd_hashtable[h].length--;
@@ -94,8 +115,8 @@ delete_from_fd(struct lws_context *context, lws_sockfd_type fd)
 	return 1;
 }
 
-LWS_VISIBLE int lws_get_random(struct lws_context *context,
-								 void *buf, int len)
+LWS_VISIBLE int
+lws_get_random(struct lws_context *context, void *buf, int len)
 {
 	int n;
 	char *p = (char *)buf;
@@ -106,7 +127,8 @@ LWS_VISIBLE int lws_get_random(struct lws_context *context,
 	return n;
 }
 
-LWS_VISIBLE int lws_send_pipe_choked(struct lws *wsi)
+LWS_VISIBLE int
+lws_send_pipe_choked(struct lws *wsi)
 {
 	/* treat the fact we got a truncated send pending as if we're choked */
 	if (wsi->trunc_len)
@@ -115,7 +137,8 @@ LWS_VISIBLE int lws_send_pipe_choked(struct lws *wsi)
 	return (int)wsi->sock_send_blocking;
 }
 
-LWS_VISIBLE int lws_poll_listen_fd(struct lws_pollfd *fd)
+LWS_VISIBLE int
+lws_poll_listen_fd(struct lws_pollfd *fd)
 {
 	fd_set readfds;
 	struct timeval tv = { 0, 0 };
@@ -129,25 +152,7 @@ LWS_VISIBLE int lws_poll_listen_fd(struct lws_pollfd *fd)
 }
 
 LWS_VISIBLE void
-lws_cancel_service(struct lws_context *context)
-{
-	struct lws_context_per_thread *pt = &context->pt[0];
-	int n = context->count_threads;
-
-	while (n--) {
-		WSASetEvent(pt->events[0]);
-		pt++;
-	}
-}
-
-LWS_VISIBLE void
-lws_cancel_service_pt(struct lws *wsi)
-{
-	struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
-	WSASetEvent(pt->events[0]);
-}
-
-LWS_VISIBLE void lwsl_emit_syslog(int level, const char *line)
+lwsl_emit_syslog(int level, const char *line)
 {
 	lwsl_emit_stderr(level, line);
 }
@@ -182,9 +187,8 @@ _lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 		context->service_tid_detected = 1;
 	}
 
-	if (timeout_ms < 0)
-	{
-			if (lws_service_flag_pending(context, tsi)) {
+	if (timeout_ms < 0) {
+		if (lws_service_flag_pending(context, tsi)) {
 			/* any socket with events to service? */
 			for (n = 0; n < (int)pt->fds_count; n++) {
 				if (!pt->fds[n].revents)
@@ -220,6 +224,9 @@ _lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 		if (n)
 			i--;
 
+		/*
+		 * any wsi has truncated, force him signalled
+		 */
 		if (wsi->trunc_len)
 			WSASetEvent(pt->events[0]);
 	}
@@ -236,29 +243,30 @@ _lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 			timeout_ms = 0;
 	}
 
-	ev = WSAWaitForMultipleEvents( 1,  pt->events , FALSE, timeout_ms, FALSE);
+	ev = WSAWaitForMultipleEvents(1, pt->events, FALSE, timeout_ms, FALSE);
 	if (ev == WSA_WAIT_EVENT_0) {
-		unsigned int eIdx;
+		unsigned int eIdx, err;
 
 		WSAResetEvent(pt->events[0]);
 
 		for (eIdx = 0; eIdx < pt->fds_count; ++eIdx) {
-			if (WSAEnumNetworkEvents(pt->fds[eIdx].fd, 0, &networkevents) == SOCKET_ERROR) {
-				lwsl_err("WSAEnumNetworkEvents() failed with error %d\n", LWS_ERRNO);
+			if (WSAEnumNetworkEvents(pt->fds[eIdx].fd, 0,
+					&networkevents) == SOCKET_ERROR) {
+				lwsl_err("WSAEnumNetworkEvents() failed "
+					 "with error %d\n", LWS_ERRNO);
 				return -1;
 			}
 
 			pfd = &pt->fds[eIdx];
 			pfd->revents = (short)networkevents.lNetworkEvents;
 
+			err = networkevents.iErrorCode[FD_CONNECT_BIT];
+
 			if ((networkevents.lNetworkEvents & FD_CONNECT) &&
-				 networkevents.iErrorCode[FD_CONNECT_BIT] &&
-				 networkevents.iErrorCode[FD_CONNECT_BIT] != LWS_EALREADY &&
-				 networkevents.iErrorCode[FD_CONNECT_BIT] != LWS_EINPROGRESS &&
-				 networkevents.iErrorCode[FD_CONNECT_BIT] != LWS_EWOULDBLOCK &&
-				 networkevents.iErrorCode[FD_CONNECT_BIT] != WSAEINVAL) {
-				lwsl_debug("Unable to connect errno=%d\n",
-					   networkevents.iErrorCode[FD_CONNECT_BIT]);
+			     err && err != LWS_EALREADY &&
+			     err != LWS_EINPROGRESS && err != LWS_EWOULDBLOCK &&
+			     err != WSAEINVAL) {
+				lwsl_debug("Unable to connect errno=%d\n", err);
 				pfd->revents |= LWS_POLLHUP;
 			}
 
@@ -269,20 +277,18 @@ _lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 			}
 			 /* if something closed, retry this slot */
 			if (pfd->revents & LWS_POLLHUP)
-					--eIdx;
+				--eIdx;
 
-			if( pfd->revents != 0 ) {
+			if (pfd->revents)
 				lws_service_fd_tsi(context, pfd, tsi);
-
-			}
 		}
 	}
 
 	context->service_tid = 0;
 
-	if (ev == WSA_WAIT_TIMEOUT) {
+	if (ev == WSA_WAIT_TIMEOUT)
 		lws_service_fd(context, NULL);
-	}
+
 	return 0;;
 }
 
@@ -309,7 +315,7 @@ lws_plat_set_socket_options(struct lws_vhost *vhost, lws_sockfd_type fd)
 		/* enable keepalive on this socket */
 		optval = 1;
 		if (setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE,
-						 (const char *)&optval, optlen) < 0)
+			       (const char *)&optval, optlen) < 0)
 			return 1;
 
 		alive.onoff = TRUE;
@@ -317,7 +323,7 @@ lws_plat_set_socket_options(struct lws_vhost *vhost, lws_sockfd_type fd)
 		alive.keepaliveinterval = vhost->ka_interval;
 
 		if (WSAIoctl(fd, SIO_KEEPALIVE_VALS, &alive, sizeof(alive),
-						  NULL, 0, &dwBytesRet, NULL, NULL))
+			     NULL, 0, &dwBytesRet, NULL, NULL))
 			return 1;
 	}
 
diff --git a/lib/pollfd.c b/lib/pollfd.c
index 8bd887fa..6af37a9a 100644
--- a/lib/pollfd.c
+++ b/lib/pollfd.c
@@ -60,13 +60,15 @@ _lws_change_pollfd(struct lws *wsi, int _and, int _or, struct lws_pollargs *pa)
 
 	pfd = &pt->fds[wsi->position_in_fds_table];
 	pa->fd = wsi->desc.sockfd;
+	lwsl_debug("%s: fd %d old events %d\n", __func__, pa->fd, pfd->events);
 	pa->prev_events = pfd->events;
 	pa->events = pfd->events = (pfd->events & ~_and) | _or;
 
 	if (wsi->http2_substream)
 		return 0;
 
-	if (wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_CHANGE_MODE_POLL_FD,
+	if (wsi->vhost &&
+	    wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_CHANGE_MODE_POLL_FD,
 					   wsi->user_space, (void *)pa, 0)) {
 		ret = -1;
 		goto bail;
@@ -113,7 +115,7 @@ _lws_change_pollfd(struct lws *wsi, int _and, int _or, struct lws_pollargs *pa)
 		}
 
 		sampled_tid = context->service_tid;
-		if (sampled_tid) {
+		if (sampled_tid && wsi->vhost) {
 			tid = wsi->vhost->protocols[0].callback(wsi,
 				     LWS_CALLBACK_GET_THREAD_ID, NULL, NULL, 0);
 			if (tid == -1) {
@@ -176,10 +178,11 @@ insert_wsi_socket_into_fds(struct lws_context *context, struct lws *wsi)
 #endif
 
 	assert(wsi);
-	assert(wsi->vhost);
+	assert(wsi->event_pipe || wsi->vhost);
 	assert(lws_socket_is_valid(wsi->desc.sockfd));
 
-	if (wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_LOCK_POLL,
+	if (wsi->vhost &&
+	    wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_LOCK_POLL,
 					   wsi->user_space, (void *) &pa, 1))
 		return -1;
 
@@ -202,7 +205,8 @@ insert_wsi_socket_into_fds(struct lws_context *context, struct lws *wsi)
 	lws_plat_insert_socket_into_fds(context, wsi);
 
 	/* external POLL support via protocol 0 */
-	if (wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_ADD_POLL_FD,
+	if (wsi->vhost &&
+	    wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_ADD_POLL_FD,
 					   wsi->user_space, (void *) &pa, 0))
 		ret =  -1;
 #ifndef LWS_NO_SERVER
@@ -212,7 +216,8 @@ insert_wsi_socket_into_fds(struct lws_context *context, struct lws *wsi)
 #endif
 	lws_pt_unlock(pt);
 
-	if (wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_UNLOCK_POLL,
+	if (wsi->vhost &&
+	    wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_UNLOCK_POLL,
 					   wsi->user_space, (void *)&pa, 1))
 		ret = -1;
 
@@ -244,7 +249,8 @@ remove_wsi_socket_from_fds(struct lws *wsi)
 	}
 #endif
 
-	if (wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_LOCK_POLL,
+	if (wsi->vhost &&
+	    wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_LOCK_POLL,
 					   wsi->user_space, (void *)&pa, 1))
 		return -1;
 
@@ -287,19 +293,21 @@ remove_wsi_socket_from_fds(struct lws *wsi)
 	wsi->position_in_fds_table = -1;
 
 	/* remove also from external POLL support via protocol 0 */
-	if (lws_socket_is_valid(wsi->desc.sockfd))
-		if (wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_DEL_POLL_FD,
-						   wsi->user_space, (void *) &pa, 0))
-			ret = -1;
+	if (lws_socket_is_valid(wsi->desc.sockfd) && wsi->vhost &&
+	    wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_DEL_POLL_FD,
+					      wsi->user_space, (void *) &pa, 0))
+		ret = -1;
+
 #ifndef LWS_NO_SERVER
-	if (!context->being_destroyed)
-		/* if this made some room, accept connects on this thread */
-		if ((unsigned int)pt->fds_count < context->fd_limit_per_thread - 1)
-			lws_accept_modulation(pt, 1);
+	if (!context->being_destroyed &&
+	    /* if this made some room, accept connects on this thread */
+	    (unsigned int)pt->fds_count < context->fd_limit_per_thread - 1)
+		lws_accept_modulation(pt, 1);
 #endif
 	lws_pt_unlock(pt);
 
-	if (wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_UNLOCK_POLL,
+	if (wsi->vhost &&
+	    wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_UNLOCK_POLL,
 					      wsi->user_space, (void *) &pa, 1))
 		ret = -1;
 #endif
@@ -314,14 +322,16 @@ lws_change_pollfd(struct lws *wsi, int _and, int _or)
 	struct lws_pollargs pa;
 	int ret = 0;
 
-	if (!wsi || !wsi->protocol || wsi->position_in_fds_table < 0)
+	if (!wsi || (!wsi->protocol && !wsi->event_pipe) ||
+	    wsi->position_in_fds_table < 0)
 		return 1;
 
 	context = lws_get_context(wsi);
 	if (!context)
 		return 1;
 
-	if (wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_LOCK_POLL,
+	if (wsi->vhost &&
+	    wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_LOCK_POLL,
 					      wsi->user_space,  (void *) &pa, 0))
 		return -1;
 
@@ -330,7 +340,8 @@ lws_change_pollfd(struct lws *wsi, int _and, int _or)
 	lws_pt_lock(pt);
 	ret = _lws_change_pollfd(wsi, _and, _or, &pa);
 	lws_pt_unlock(pt);
-	if (wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_UNLOCK_POLL,
+	if (wsi->vhost &&
+	    wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_UNLOCK_POLL,
 					   wsi->user_space, (void *) &pa, 0))
 		ret = -1;
 
diff --git a/lib/private-libwebsockets.h b/lib/private-libwebsockets.h
index 144258a9..a723d162 100644
--- a/lib/private-libwebsockets.h
+++ b/lib/private-libwebsockets.h
@@ -634,6 +634,7 @@ enum connection_mode {
 	LWSCM_CGI, /* stdin, stdout, stderr for another cgi master wsi */
 	LWSCM_RAW, /* raw with bulk handling */
 	LWSCM_RAW_FILEDESC, /* raw without bulk handling */
+	LWSCM_EVENT_PIPE, /* event pipe with no vhost or protocol binding */
 
 	/* HTTP Client related */
 	LWSCM_HTTP_CLIENT = LWSCM_FLAG_IMPLIES_CALLBACK_CLOSED_CLIENT_HTTP,
@@ -894,9 +895,10 @@ struct lws_context_per_thread {
 	unsigned char *serv_buf;
 #ifdef _WIN32
 	WSAEVENT *events;
-#else
-	lws_sockfd_type dummy_pipe_fds[2];
 #endif
+	lws_sockfd_type dummy_pipe_fds[2];
+	struct lws *pipe_wsi;
+
 	unsigned int fds_count;
 	uint32_t ah_pool_length;
 
@@ -1993,6 +1995,7 @@ struct lws {
 	unsigned int cgi_stdout_zero_length:1;
 	unsigned int seen_zero_length_recv:1;
 	unsigned int rxflow_will_be_applied:1;
+	unsigned int event_pipe:1;
 
 #if defined(LWS_WITH_ESP8266)
 	unsigned int pending_send_completion:3;
@@ -2616,6 +2619,15 @@ void lws_free(void *p);
 #define lws_free_set_NULL(P)	do { lws_realloc(P, 0, "free"); (P) = NULL; } while(0)
 #endif
 
+int
+lws_plat_pipe_create(struct lws *wsi);
+int
+lws_plat_pipe_signal(struct lws *wsi);
+void
+lws_plat_pipe_close(struct lws *wsi);
+int
+lws_create_event_pipes(struct lws_context *context);
+
 const struct lws_plat_file_ops *
 lws_vfs_select_fops(const struct lws_plat_file_ops *fops, const char *vfs_path,
 		    const char **vpath);
diff --git a/lib/service.c b/lib/service.c
index 81321a26..ec3b14f2 100644
--- a/lib/service.c
+++ b/lib/service.c
@@ -1167,6 +1167,7 @@ lws_service_fd_tsi(struct lws_context *context, struct lws_pollfd *pollfd, int t
 
 	/* no, here to service a socket descriptor */
 	wsi = wsi_from_fd(context, pollfd->fd);
+
 	if (!wsi)
 		/* not lws connection ... leave revents alone and return */
 		return 0;
@@ -1221,6 +1222,47 @@ lws_service_fd_tsi(struct lws_context *context, struct lws_pollfd *pollfd, int t
 	/* okay, what we came here to do... */
 
 	switch (wsi->mode) {
+	case LWSCM_EVENT_PIPE:
+	{
+		struct lws_vhost *v = context->vhost_list;
+		char s[10];
+
+		/*
+		 * discard the byte(s) that signaled us
+		 * We really don't care about the number of bytes, but coverity
+		 * thinks we should.
+		 */
+		n = read(wsi->desc.sockfd, s, sizeof(s));
+		(void)n;
+		if (n < 0)
+			goto close_and_handled;
+
+		/*
+		 * the poll() wait, or the event loop for libuv etc is a
+		 * process-wide resource that we interrupted.  So let every
+		 * protocol that may be interested in the pipe event know that
+		 * it happened.
+		 */
+		while (v) {
+			const struct lws_protocols *p = v->protocols;
+			wsi->vhost = v;
+
+			for (n = 0; n < v->count_protocols; n++) {
+				wsi->protocol = p;
+				if (p->callback && p->callback(wsi,
+					  LWS_CALLBACK_EVENT_WAIT_CANCELLED,
+					  NULL, NULL, 0)) {
+					lwsl_info("closed in event cancel\n");
+					goto close_and_handled;
+				}
+				p++;
+			}
+			v = v->vhost_next;
+		}
+		wsi->vhost = NULL;
+		wsi->protocol = NULL;
+		goto handled;
+	}
 	case LWSCM_HTTP_SERVING:
 	case LWSCM_HTTP_CLIENT:
 	case LWSCM_HTTP_SERVING_ACCEPTED:
diff --git a/plugins/protocol_lws_mirror.c b/plugins/protocol_lws_mirror.c
index 90b5faa9..8affca99 100644
--- a/plugins/protocol_lws_mirror.c
+++ b/plugins/protocol_lws_mirror.c
@@ -402,6 +402,10 @@ req_writable:
 		mirror_callback_all_in_mi_on_writable(pss->mi);
 		break;
 
+	case LWS_CALLBACK_EVENT_WAIT_CANCELLED:
+		lwsl_notice("LWS_CALLBACK_EVENT_WAIT_CANCELLED\n");
+		break;
+
 	default:
 		break;
 	}
diff --git a/test-apps/test-server-libuv.c b/test-apps/test-server-libuv.c
index c8b305f6..de9c11e5 100644
--- a/test-apps/test-server-libuv.c
+++ b/test-apps/test-server-libuv.c
@@ -168,6 +168,15 @@ static void timer_cb(uv_timer_t *t)
 	}
 }
 
+static void timer_test_cancel_cb(uv_timer_t *h)
+{
+	if (context) {
+		lwsl_notice("(doing cancel test)\n");
+		lws_cancel_service(context);
+	}
+}
+
+
 static void timer_close_cb(uv_handle_t *h)
 {
 	lwsl_notice("timer close cb %p, loop has %d handles\n",
@@ -205,6 +214,7 @@ int main(int argc, char **argv)
 	uv_timer_t timer_outer;
 	struct counter ctr;
 	int foreign_libuv_loop = 0;
+	uv_timer_t timer_test_cancel;
 /* <--- only needed for foreign loop test --- */
 #endif
 	const char *iface = NULL;
@@ -351,6 +361,9 @@ int main(int argc, char **argv)
 		uv_signal_init(&loop, &signal_outer);
 		uv_signal_start(&signal_outer, outer_signal_cb, SIGINT);
 
+		uv_timer_init(&loop, &timer_test_cancel);
+		uv_timer_start(&timer_test_cancel, timer_test_cancel_cb, 2000, 2000);
+
 		uv_timer_init(&loop, &timer_outer);
 		timer_outer.data = &ctr;
 		ctr.cur = 0;
@@ -374,10 +387,10 @@ int main(int argc, char **argv)
 	lws_uv_sigint_cfg(context, 1, signal_cb);
 
 #if UV_VERSION_MAJOR > 0
-	if (foreign_libuv_loop)
+	if (foreign_libuv_loop) {
 		/* we have our own uv loop outside of lws */
 		lws_uv_initloop(context, &loop, 0);
-	else
+	} else
 #endif
 	{
 		/*
@@ -438,6 +451,7 @@ int main(int argc, char **argv)
 		 *          outside of lws */
 
 		uv_timer_stop(&timer_outer);
+		uv_timer_stop(&timer_test_cancel);
 		uv_close((uv_handle_t*)&timer_outer, timer_close_cb);
 		uv_signal_stop(&signal_outer);
 
diff --git a/test-apps/test-server.c b/test-apps/test-server.c
index 1d36f9e0..105d4881 100644
--- a/test-apps/test-server.c
+++ b/test-apps/test-server.c
@@ -174,6 +174,7 @@ void sighandler(int sig)
 		 * port + 1
 		 */
 		dynamic_vhost_enable ^= 1;
+		lws_cancel_service(context);
 		lwsl_notice("SIGUSR1: dynamic_vhost_enable: %d\n",
 				dynamic_vhost_enable);
 		return;