extern BOOL directory_make(uschar *, uschar *, int, BOOL);
extern dns_address *dns_address_from_rr(dns_answer *, dns_record *);
extern void dns_build_reverse(uschar *, 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 **);
extern BOOL directory_make(uschar *, uschar *, int, BOOL);
extern dns_address *dns_address_from_rr(dns_answer *, dns_record *);
extern void dns_build_reverse(uschar *, 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 **);