dns_mx - look up Mail eXchanger

       dns_mx  looks  up MX records for the fully-qualified domain name in fqdn. It puts the MX records into out
       and returns 0. Each MX record is a two-byte MX distance (big endian) followed  by  a  \0-terminated  dot-
       encoded domain name. If the domain does not exist in DNS, or has no MX records, out will be empty.

       If  dns_mx  has  trouble  with  the  DNS  lookup  or  runs  out  of  memory, it returns -1, setting errno
       appropriately. It may or may not change out.

       dns_mx - look up Mail eXchanger

dns_mx_packet(3), dns_ip4(3), dns_ip6(3)

                                                                                                       dns_mx(3)

#include<libowfat/dns.h>

       int dns_mx(stralloc* out,stralloc* fqdn);