+#ifdef KERNEL
+void putbuf (const char *, size_t);
+#endif
+#ifdef USER
+int hprintf (int, const char *, ...) PRINTF_FORMAT (2, 3);
+int vhprintf (int, const char *, va_list) PRINTF_FORMAT (2, 0);
+#endif
+void hex_dump (uintptr_t ofs, const void *, size_t size, bool ascii);