diff --git a/test/test-tty.c b/test/test-tty.c
index eb5d5df5..f3003efa 100644
--- a/test/test-tty.c
+++ b/test/test-tty.c
@@ -30,6 +30,9 @@
 # include <unistd.h>
 #endif
 
+#include <string.h>
+#include <errno.h>
+
 
 TEST_IMPL(tty) {
   int r, width, height;
@@ -62,7 +65,12 @@ TEST_IMPL(tty) {
 
 #else /* unix */
   ttyin_fd = open("/dev/tty", O_RDONLY, 0);
+  if (ttyin_fd < 0)
+    LOGF("Cannot open /dev/tty as read-only: %s\n", strerror(errno));
+
   ttyout_fd = open("/dev/tty", O_WRONLY, 0);
+  if (ttyout_fd < 0)
+    LOGF("Cannot open /dev/tty as write-only: %s\n", strerror(errno));
 #endif
 
   ASSERT(ttyin_fd >= 0);