4 files changed, 12 insertions, 8 deletions
diff --git a/src/core/aio.c b/src/core/aio.c
index 73c1dd9b..c6512eb4 100644
--- a/src/core/aio.c
+++ b/src/core/aio.c
@@ -206,14 +206,14 @@ nni_aio_cancel(nni_aio *aio, int rv)
 
 // I/O provider related functions.
 
-void
+int
 nni_aio_finish(nni_aio *aio, int result, size_t count)
 {
 	nni_mtx_lock(&aio->a_lk);
 	if (aio->a_flags & (NNI_AIO_DONE | NNI_AIO_FINI)) {
 		// Operation already done (canceled or timed out?)
 		nni_mtx_unlock(&aio->a_lk);
-		return;
+		return (NNG_ESTATE);
 	}
 	aio->a_flags |= NNI_AIO_DONE;
 	aio->a_result      = result;
@@ -228,6 +228,7 @@ nni_aio_finish(nni_aio *aio, int result, size_t count)
 
 	nni_taskq_dispatch(NULL, &aio->a_tqe);
 	nni_mtx_unlock(&aio->a_lk);
+	return (0);
 }
 
 void
@@ -307,7 +308,7 @@ nni_aio_expire_loop(void *arg)
 	nni_list *aios = &nni_aio_expire_aios;
 	nni_aio * aio;
 	nni_time  now;
-	int       rv;
+
 	void (*cancelfn)(nni_aio *);
 
 	NNI_ARG_UNUSED(arg);
diff --git a/src/core/aio.h b/src/core/aio.h
index 09923d7f..4f190aa1 100644
--- a/src/core/aio.h
+++ b/src/core/aio.h
@@ -104,8 +104,12 @@ extern int  nni_aio_list_active(nni_aio *);
 
 // nni_aio_finish is called by the provider when an operation is complete.
 // The provider gives the result code (0 for success, an NNG errno otherwise),
-// and the amount of data transferred (if any).
-extern void nni_aio_finish(nni_aio *, int, size_t);
+// and the amount of data transferred (if any).  If the return code is
+// non-zero, it indicates that the operation failed (usually because the aio
+// was already canceled.)  This is important for providers that need to
+// prevent resources (new pipes for example) from accidentally leaking
+// during close operations.
+extern int nni_aio_finish(nni_aio *, int, size_t);
 
 // nni_aio_cancel is used to cancel an operation.  Any pending I/O or
 // timeouts are canceled if possible, and the callback will be returned
diff --git a/src/core/endpt.c b/src/core/endpt.c
index 4ed678d7..8048de2b 100644
--- a/src/core/endpt.c
+++ b/src/core/endpt.c
@@ -397,7 +397,7 @@ nni_ep_accept_start(nni_ep *ep)
 	if (ep->ep_closed) {
 		return;
 	}
-
+	aio->a_pipe  = NULL;
 	aio->a_endpt = ep->ep_data;
 	ep->ep_ops.ep_accept(ep->ep_data, aio);
 }
diff --git a/src/core/socket.c b/src/core/socket.c
index 7ec383d4..10bc1c80 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -124,8 +124,7 @@ nni_sock_pipe_ready(nni_sock *sock, nni_pipe *pipe)
 void
 nni_sock_pipe_remove(nni_sock *sock, nni_pipe *pipe)
 {
-	void *  pdata;
-	nni_ep *ep;
+	void *pdata;
 
 	pdata = nni_pipe_get_proto_data(pipe);