void *mh_xcalloc(size_t, size_t);
void mh_free0(void *);
char *pwd(void);
-char *add(char *, char *);
+char *add(const char *, char *);
void create_folder(char *, int, void (*)(int));
int num_digits(int);
-char *mh_xstrdup(char *);
+char *mh_xstrdup(const char *);
struct msgs_array {
int max, size;