extern int cmd_checkout_index(int argc, const char **argv, const char *prefix);
extern int cmd_check_attr(int argc, const char **argv, const char *prefix);
extern int cmd_check_ref_format(int argc, const char **argv, const char *prefix);
extern int cmd_checkout_index(int argc, const char **argv, const char *prefix);
extern int cmd_check_attr(int argc, const char **argv, const char *prefix);
extern int cmd_check_ref_format(int argc, const char **argv, const char *prefix);