diff --git a/scripts/echo.c b/scripts/echo.c
index 8c6b409d3..7474ccdd4 100644
--- a/scripts/echo.c
+++ b/scripts/echo.c
@@ -27,6 +27,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <limits.h>
+#include <unistd.h>
 
 #define WANT_HEX_ESCAPES 1