Libwebsockets is a lightweight pure C library built to use minimal CPU and
memory resources, and provide fast throughput in both directions as client or
server.

libwebsockets features
- Provides server and client APIs for RFC6455 v13 ws:// and wss://
  websocket protocol, along with http:// and https://
- Can be configured to use OpenSSL, CyaSSL, or WolfSSL to provide fully
  encrypted client and server links - including client certificate support
- Lightweight and fast even at 250K connections per thread and beyond -
  - performance per byte and performance per MIPS many times better than
  traditional solutions
- CMake based project that has been used in a variety of OS contexts including
  Linux (uclibc and glibc), ARM-based embedded boards, MBED3, MIPS / OpenWRT,
  Windows, Android, Apple iOS and even Tivo. It's used all over the place
  including The New York Times customer-facing servers and BMW.
- It includes a stub webserver that is enough to deliver your scripts to the
  browser that open websocket connections back to the same server, so it can
  solve the entire server side, ws://, wss://, http://, and https:// in one
  step. Apache, Java or any other server-side support is not needed.
- Compliant browsers from the last few years are supported on any platform.
- Full-strength SSL suport (test server is A+ on SSLLABS test)
