extern int cmd_diff_index(int argc, const char **argv, const char *prefix);
extern int cmd_diff(int argc, const char **argv, const char *prefix);
extern int cmd_diff_tree(int argc, const char **argv, const char *prefix);
+extern int cmd_difftool(int argc, const char **argv, const char *prefix);
extern int cmd_fast_export(int argc, const char **argv, const char *prefix);
extern int cmd_fetch(int argc, const char **argv, const char *prefix);
extern int cmd_fetch_pack(int argc, const char **argv, const char *prefix);