diff --git a/mace/examples/cli/example.cc b/mace/examples/cli/example.cc
index 8ab0b0d4a6852e37af8d2bf894e494d17792724b..8bcef97ae9cb8271c18c50881c6af085bd540484 100644
--- a/mace/examples/cli/example.cc
+++ b/mace/examples/cli/example.cc
@@ -13,6 +13,7 @@
 // limitations under the License.
 
 #include <dirent.h>
+#include <errno.h>
 #include <fcntl.h>
 #include <malloc.h>
 #include <sys/mman.h>