Book Image

Hands-On Network Programming with C

By : Lewis Van Winkle
Book Image

Hands-On Network Programming with C

By: Lewis Van Winkle

Overview of this book

Network programming enables processes to communicate with each other over a computer network, but it is a complex task that requires programming with multiple libraries and protocols. With its support for third-party libraries and structured documentation, C is an ideal language to write network programs. Complete with step-by-step explanations of essential concepts and practical examples, this C network programming book begins with the fundamentals of Internet Protocol, TCP, and UDP. You’ll explore client-server and peer-to-peer models for information sharing and connectivity with remote computers. The book will also cover HTTP and HTTPS for communicating between your browser and website, and delve into hostname resolution with DNS, which is crucial to the functioning of the modern web. As you advance, you’ll gain insights into asynchronous socket programming and streams, and explore debugging and error handling. Finally, you’ll study network monitoring and implement security best practices. By the end of this book, you’ll have experience of working with client-server applications and be able to implement new network programs in C. The code in this book is compatible with the older C99 version as well as the latest C18 and C++17 standards. You’ll work with robust, reliable, and secure code that is portable across operating systems, including Winsock sockets for Windows and POSIX sockets for Linux and macOS.
Table of Contents (26 chapters)
Title Page
Dedication
About Packt
Contributors
Preface
Index

Content types


It is the HTTP server's job to tell its client the type of content being sent. This is done by the Content-Type header. The value of the Content-Type header should be a valid media type (formerly known as the MIME type) registered with the Internet Assigned Numbers Authority (IANA). See the Further reading section of this chapter for a link to the IANA list of media types.

There are a few ways to determine the media type of a file. If you're on a Unix-based system, such as Linux or macOS, then your operating system already provides a utility for this.

Try the following command on Linux or macOS (replace example.txt with a real filename):

file --mime-type example.txt

The following screenshot shows its usage:

As you can see in the preceding screenshot, the file utility told us the media type of index.html is text/html. It also said the media type of smile.png is image/png, and the media type of test.txt is text/plain.

Our web server just uses the file's extension to determine the media...