--- /dev/null
+#define DEBUG
+#define PORT "64010"
+#define main real_main
+int real_main(void);
+#include "run-10-many.c"
+#undef main
+/* We stack overflow if we debug all of them! */
+static bool debug_one(struct io_conn *conn)
+{
+ return conn == buf[1].reader;
+}
+int main(void) { io_debug = debug_one; return real_main(); }