diff --git a/submodule.h b/submodule.h
--- /dev/null
+++ b/submodule.h
@@ -0,0 +1,8 @@
+#ifndef SUBMODULE_H
+#define SUBMODULE_H
+
+void show_submodule_summary(FILE *f, const char *path,
+ unsigned char one[20], unsigned char two[20],
+ const char *del, const char *add, const char *reset);
+
+#endif