The code developed in this chapter is suitable for use in trusted applications on trusted networks. For example, if you are developing a video game, it can be very useful to make it serve a web page that displays debugging information. This doesn't have to be a security concern, as it can limit connections to the local machine.
If you must deploy a web server on the internet, I suggest you consider using a free and open source implementation that's already available. The web servers Nginx and Apache, for example, are highly performant, cross-platform, secure, written in C, and completely free. They are also well-documented and easy to find support for.
If you want to expose your program to the internet, you can communicate to a web server using either CGI or FastCGI. With CGI, the web server handles the HTTP request. When a request comes in, it runs your program and returns your program's output in the HTTP response body.
Alternatively, many web servers (such as Nginx or Apache) work as a reverse proxy. This essentially puts the web server between your code and the internet. The web server accepts and forwards HTTP messages to your HTTP server. This can have the effect of slightly shielding your code from attackers.