extern int dns_lookup(dns_answer *, const uschar *, int, const uschar **);
extern void dns_pattern_init(void);
extern int dns_special_lookup(dns_answer *, const uschar *, int, const uschar **);
extern int dns_lookup(dns_answer *, const uschar *, int, const uschar **);
extern void dns_pattern_init(void);
extern int dns_special_lookup(dns_answer *, const uschar *, int, const uschar **);