This project demonstrates work with socket LINUX API and is limited on Linux, or macOS operating systems. It started by following book Hands-On Network Programming with C: Learn socket programming in C and write secure and optimized network code and most code is taken from there (check its github page).

Creates a server listening on socket using TCP, or UDP protocol. They are following:

• tcp_ping_server - responds to any incomming message with pong
• udp_ping_server
• tcp_broadcast - broadcasts messages received from client to all other clients

Resolves a IP address for a domain name

• dns_lookup - resolve domain name using OS API
• dns_raw_lookup - resolves domain name manually creating UDP message

Read DNS Query to learn how to compose DNS message

• make install - installs all applications to build folder - ./build
• make <application> - installs specific application (see Applications) - make udp_ping_server

example on how to run a application:

./build/dns_lookup google.com
  resolving hostname=google.com
  2a00:1450:4009:807::200e 0
  2a00:1450:4009:807::200e 0
  216.58.204.238 0
  216.58.204.238 0