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

Chapter 4, Establishing UDP Connections

  1. How do sendto() and recvfrom() differ from send() and recv()?

The send() and recv() functions are useful after calling connect(). They only work with the one remote address that was passed to connect(). The sendto() and recvfrom() functions can be used with multiple remote addresses.

  1. Can send() and recv() be used on UDP sockets?

Yes. The connect() function should be called first in that case. However, the sendto() and recvfrom() functions are often more useful for UDP sockets.

  1. What does connect() do in the case of a UDP socket?

The connect() function associates the socket with a remote address.

  1. What makes multiplexing with UDP easier than with TCP?

One UDP socket can talk to multiple remote peers. For TCP, one socket is needed for each peer.

  1. What are the downsides to UDP when compared to TCP?

UDP does not attempt to fix many of the errors that TCP does. For example, TCP ensures that data arrives in the same order it was sent, TCP tries to avoid causing network congestion, and TCP attempts to resend lost packets. UDP does none of this.

  1. Can the same program use UDP and TCP?

Yes. It just needs to create sockets for both.