text: #ifndef _DNS_H_
  #define _DNS_H_ 1
  
  #include <stdint.h>
  
  typedef struct {
      int v;
      union {
         unsigned char v4[4];
         unsigned char v6[16];
      } data;
  } addr_t;
  
  typedef struct {
    int port;
    int datattl;
    int nsttl;
    const char *host;
    const char *ns;
    const char *mbox;
    int (*cb)(void *opt, char *requested_hostname, addr_t *addr, int max, int ipv4, int ipv6);
    // stats
    uint64_t nRequests;
  } dns_opt_t;
  
  extern int dnsserver(dns_opt_t *opt);
  
  #endif
  