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
About Packt

HTTP POST requests

An HTTP POST request sends data from the web client to the web server. Unlike an HTTP GET request, a POST request includes a body containing data (although this body could be zero-length).

The POST body format can vary, and it should be identified by a Content-Type header. Many modern, web-based APIs expect a POST body to be JSON encoded.

Consider the following HTTP POST request:

POST /orders HTTP/1.1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:64.0)
Content-Type: application/json
Content-Length: 56
Connection: close


In the preceding example, you can see that the HTTP POST request is similar to an HTTP GET request. Notable differences are as follows: the request starts with POST instead of GET; a Content-Type header field is included; a Content-Length header field is present; and an HTTP message body is included. In that example, the HTTP message body is in JSON format, as specified by...