extern void dns_init(BOOL, BOOL);
extern int dns_basic_lookup(dns_answer *, uschar *, int);
extern int dns_lookup(dns_answer *, uschar *, int, uschar **);
extern void dns_init(BOOL, BOOL);
extern int dns_basic_lookup(dns_answer *, uschar *, int);
extern int dns_lookup(dns_answer *, uschar *, int, uschar **);