Listing network adapters from C

Sometimes, it is useful for your C programs to know what your local address is. For most of this book, we are able to write code that works both on Windows and Unix-based (Linux and macOS) systems. However, the API for listing local addresses is very different between systems. For this reason, we split this program into two: one for Windows and one for Unix-based systems.

We will address the Windows case first.

Listing network adapters on Windows

The Windows networking API is called Winsock, and we will go into much more detail about it in the next chapter.

Whenever we are using Winsock, the first thing we must do is initialize it. This is done with a call to WSAStartup(). Here is a small C...