ZMap is a fast single packet network scanner for network surveys
...ZDNS is a utility for performing fast DNS lookups, such as completing an A lookup for all names in a zone file, or collecting CAA records for a large number of websites. ZDNS contains its own recursive resolver and supports A, AAAA, ANY, AXFR, CAA, CNAME, DMARC, MX, NS, PTR, TXT, etc.
The Validating Stub Resolver (vsResolver) is a DNS stub resolver that implements the Domain Name System Security Extensions (DNSSEC) specified in RFC 4033, RFC 4034 and RFC 4035. These add data origin authentication and data integrity to the Domain Name System. vsResolver extends the dnspython toolkit (http://www.dnspython.org/) and uses the pycrypto library for its underlying crypto implementation(https://www.dlitz.net/software/pycrypto/).
A DNS resolver library written in pure PHP script. This library offers almost same functionalities of getmxrr() and checkdnsrr(). You may find this library helpful when you would like to retrieve MX(Mail exchange) records in win32 PHP environment.