diff --git a/unix/input.c b/unix/input.c
index 4d856f2ff89d663fa43476bb42c7fe7c60d5dbdc..19ca649c9fe5a024434942240d583e1040a261db 100644
--- a/unix/input.c
+++ b/unix/input.c
@@ -41,8 +41,6 @@
 #include <readline/history.h>
 #endif
 
-#define CTRL_D  '\x04'
-
 char *prompt(char *p) {
 #if MICROPY_USE_READLINE
     char *line = readline(p);