char *mutt_strlower (char *);
char *mutt_substrcpy (char *, const char *, const char *, size_t);
char *mutt_substrdup (const char *, const char *);
char *mutt_strlower (char *);
char *mutt_substrcpy (char *, const char *, const char *, size_t);
char *mutt_substrdup (const char *, const char *);