diff --git a/TODO.md b/TODO.md
index 281aec4..a171034 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,6 +1,5 @@
 LibuEv TODO
 ===========
 
-* Add uev_*_start(), at least for I/O, needed by finit
 * Make port to *BSD kqueue API, http://en.wikipedia.org/wiki/Kqueue
 
diff --git a/io.c b/io.c
index 7dfa15f..e0483c2 100644
--- a/io.c
+++ b/io.c
@@ -23,6 +23,8 @@
  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
+#include <errno.h>
+
 #include "uev.h"
 
 
@@ -39,12 +41,14 @@
  */
 int uev_io_init(uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int fd, int events)
 {
+	if (fd < 0) {
+		errno = EINVAL;
+		return -1;
+	}
+
 	if (uev_watcher_init(ctx, w, UEV_IO_TYPE, cb, arg, fd, events))
 		return -1;
 
-	if (fd < 0)
-		return 0;
-
 	return uev_watcher_start(w);
 }
 
@@ -67,15 +71,28 @@ int uev_io_set(uev_t *w, int fd, int events)
 	return uev_io_init(w->ctx, w, (uev_cb_t *)w->cb, w->arg, fd, events);
 }
 
+/**
+ * Start an I/O watcher
+ * @param w  Watcher to start (again)
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_io_start(uev_t *w)
+{
+	return uev_io_set(w, w->fd, w->events);
+}
+
 /**
  * Stop an I/O watcher
- * @param w  Pointer to an uev_t watcher
+ * @param w  Watcher to stop
  *
  * @return POSIX OK(0) or non-zero with @param errno set on error.
  */
 int uev_io_stop(uev_t *w)
 {
-	return uev_watcher_stop(w);
+	int status = uev_watcher_stop(w);
+
+	return status;
 }
 
 /**
diff --git a/signal.c b/signal.c
index a94660f..6dc0a8b 100644
--- a/signal.c
+++ b/signal.c
@@ -46,6 +46,12 @@ int uev_signal_init(uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int signo
 	int fd;
 	sigset_t mask;
 
+	if (!w || !ctx) {
+		errno = EINVAL;
+		return -1;
+	}
+	w->fd = -1;
+
 	sigemptyset(&mask);
 	fd = signalfd(-1, &mask, SFD_NONBLOCK);
 	if (fd < 0)
@@ -81,6 +87,9 @@ int uev_signal_set(uev_t *w, int signo)
 		return -1;
 	}
 
+	/* Remember for callbacks and start/stop */
+	w->signo = signo;
+
 	/* Handle stopped signal watchers */
 	if (w->fd < 0) {
 		/* Remove from internal list */
@@ -104,6 +113,26 @@ int uev_signal_set(uev_t *w, int signo)
 	return uev_watcher_start(w);
 }
 
+
+/**
+ * Start a stopped signal watcher
+ * @param w  Watcher to start (again)
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_signal_start(uev_t *w)
+{
+	if (!w) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if (-1 != w->fd)
+		uev_signal_stop(w);
+
+	return uev_signal_set(w, w->signo);
+}
+
 /**
  * Stop a signal watcher
  * @param w  Watcher to stop
diff --git a/timer.c b/timer.c
index fdbba81..753862d 100644
--- a/timer.c
+++ b/timer.c
@@ -130,6 +130,25 @@ int uev_timer_set(uev_t *w, int timeout, int period)
 	return 0;
 }
 
+/**
+ * Start a stopped timer watcher
+ * @param w  Watcher to start (again)
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_timer_start(uev_t *w)
+{
+	if (!w) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if (-1 != w->fd)
+		uev_watcher_stop(w);
+
+	return uev_timer_set(w, w->timeout, w->period);
+}
+
 /**
  * Stop and unregister a timer watcher
  * @param w  Watcher to stop
diff --git a/uev.c b/uev.c
index 4b6f492..24696f4 100644
--- a/uev.c
+++ b/uev.c
@@ -231,8 +231,6 @@ int uev_run(uev_ctx_t *ctx, int flags)
 
 				if (read(w->fd, &fdsi, sz) != sz)
 					goto exit;
-
-				w->signo = fdsi.ssi_signo;
 			}
 
 			if (w->cb)
diff --git a/uev.h b/uev.h
index 6ae5f79..f864e2d 100644
--- a/uev.h
+++ b/uev.h
@@ -98,14 +98,17 @@ int uev_run            (uev_ctx_t *ctx, int flags);
 
 int uev_io_init        (uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int fd, int events);
 int uev_io_set         (uev_t *w, int fd, int events);
+int uev_io_start       (uev_t *w);
 int uev_io_stop        (uev_t *w);
 
 int uev_timer_init     (uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int timeout, int period);
 int uev_timer_set      (uev_t *w, int timeout, int period);
+int uev_timer_start    (uev_t *w);
 int uev_timer_stop     (uev_t *w);
 
 int uev_signal_init    (uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int signo);
 int uev_signal_set     (uev_t *w, int signo);
+int uev_signal_start   (uev_t *w);
 int uev_signal_stop    (uev_t *w);
 
 #endif /* LIBUEV_UEV_H_ */