C Programming for System, Network, and Cloud Engineers Techniques for Processes, Memory, Network Applications, and Linux… (Anil Kumar Rangisetti)（Z-Library）

C Programming for System, Network, and Cloud Engineers Techniques for Processes, Memory, Network Applications, and Linux Namespaces — Dr Anil Kumar Rangisetti

C Programming for System, Network, and Cloud Engineers Techniques for Processes, Memory, Network Applications, and Linux Namespaces Dr Anil Kumar Rangisetti

C Programming for System, Network, and Cloud Engineers: Techniques for Processes, Memory, Network Applications, and Linux Namespaces ISBN-13 (pbk): 979-8-8688-1804-2 ISBN-13 (electronic): 979-8-8688-1805-9 https://doi.org/10.1007/979-8-8688-1805-9 Copyright © 2026 by Dr Anil Kumar Rangisetti This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Trademarked names, logos, and images may appear in this book. Rather than use a trademark symbol with every occurrence of a trademarked name, logo, or image we use the names, logos, and images only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark. The use in this publication of trade names, trademarks, service marks, and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Managing Director, Apress Media LLC: Welmoed Spahr Acquisitions Editor: Melissa Duffy Editorial Assistant: Gryffin Winkler Cover designed by eStudioCalamar Cover image designed by Niklas Bischop on unsplash.com Distributed to the book trade worldwide by Springer Science+Business Media New York, 1 New York Plaza, New York, NY 10004. Phone 1-800-SPRINGER, fax (201) 348-4505, e-mail orders-ny@springer-sbm.com, or visit www.springeronline.com. Apress Media, LLC is a Delaware LLC and the sole member (owner) is Springer Science + Business Media Finance Inc (SSBM Finance Inc). SSBM Finance Inc is a Delaware corporation. For information on translations, please e-mail booktranslations@springernature.com; for reprint, paperback, or audio rights, please e-mail bookpermissions@springernature.com. Apress titles may be purchased in bulk for academic, corporate, or promotional use. eBook versions and licenses are also available for most titles. For more information, reference our Print and eBook Bulk Sales web page at http://www.apress.com/bulk-sales. Any source code or other supplementary material referenced by the author in this book is available to readers on GitHub. For more detailed information, please visit https://www.apress.com/gp/services/ source-code. If disposing of this product, please recycle the paper Dr Anil Kumar Rangisetti Opp G Pullareddy Engineering College Balaji Villas 3rd Phase, A Blk, Plot A65 Kurnool, Andhra Pradesh, India

To all my teachers, especially Dr. Bheemarjuna Reddy and Shri Badrinadh, for identifying my strengths, giving me wonderful opportunities to work with them, and guiding me to achieve my goals. To my lovely wife, Sravani, for being a wonderful partner and supporting me in all situations. Without her love and support, I could not have accomplished this work. —Dr. Anil Kumar Rangisetti

xiii About the Author Dr. Anil Kumar Rangisetti received his PhD in the field of computer science and engineering from IIT Hyderabad, India. He has 13 years of teaching and research experience in computer science and engineering. During his career, he worked at prestigious Indian institutions, such as IIIT Dharwad, SRM-AP, and GMR, and worked at software development and research labs such as ARICENT and IRL-Delhi. Currently he is working as assistant professor in the Department of CSE, IIITDM, Kurnool. He trained many students in programming languages and in the use of advanced simulators (NS-3), Docker, and networking tools for researching and developing applications at his workplaces. He guided a significant number of undergraduate and postgraduate students for project works. Broadly, his research interests include Wi-Fi technologies, next-generation mobile networks, SDN, NFV, and cloud computing. He authored a number of novel research publications with IEEE, Springer, Elsevier, and Wiley in the field of a variety of networking technologies such as LTE, SDN and NFV, and Wi-Fi technologies. He authored various practical books related to network simulations, future networking technologies, and programming languages. He brings with him academic and professional experience, which includes time spent at Aricent and the IBM research lab. Additionally, he enjoys writing and reviewing books on systems and networking technologies, mobile and wireless networks, cloud computing technologies, and programming languages.

xv German Gonzalez-Morris is a polyglot software architect/ engineer with 20+ years in the field, with knowledge in Java, SpringBoot, C/C++, Julia, Python, Haskell, and Javascript, among others. He works with cloud (architecture) web- distributed applications and microservices. German loves math puzzles (including reading Knuth, and is proud of solving some of Don’s puzzles), swimming, and table tennis. Also, he has reviewed several books, including books on application containers (WebLogic) and programming languages (C, Java, Spring, Python, Haskell, Typescript, WebAssembly, Math for coders, regexp, Julia, data structures and algorithms, and Kafka).    About the Technical Reviewer

xvii Acknowledgments First of all, I would like to thank Apress for believing my book idea and giving me this wonderful opportunity. I would especially like to thank Melissa Duffy for keenly going through the book proposal and suggesting to me how to make the book proposal interesting and perfect. Melissa’s support and encouragement throughout the book writing process has been wonderful. All of Melissa’s suggestions helped in improving the quality of the book’s content. I would like to thank Krishnan Sathyamurthy for his constant support in the entire review and finalization of the book’s content. Krishnan’s timely help and support helped me to complete all works in time. A big thanks to the technical reviewer of the book for his valuable time and suggestions in all hands-on activities and technical concepts of the book. His keen observations helped me a lot in correcting all kinds of errors and incorporating necessary topics to improve the quality of the book tremendously. I would like to thank each and every member of the Apress team for supporting me in writing this wonderful book and completing it successfully and happily. I would love to work with the Apress team again and again. My heartfelt thanks to all my students for their interest in attending my lectures and working with me. All my students’ curiosity, comments, and suggestions helped me to write this wonderful book. Finally, I would like to thank all my family members, friends, and colleagues for their love and support always.

xix Introduction C programming is known for developing systems software (operating systems, databases, network protocol stack, and virtualization technologies) and applications by efficiently utilizing system computational resources. In this book you will be exploring C programming key skills such as handling functions, arrays, strings, unions, pointers, and memory. While learning these key skills, you will be exploring important runtime error handling techniques and best practices to implement reliable and efficient C programs. It is necessary to develop runtime errors and performance handling code in your C applications before deploying them in the runtime environment. Otherwise your programs/applications can crash the system and/or be damaged by other malicious or error-prone applications. In order to help you in thinking of a runtime environment and handling possible issues, this book introduces and discusses how to use important open- source Linux tools (gcc, gdb, gcov, valgrind) for compilation, linking, debugging, code coverage, and handling memory leaks. This book’s chapters are organized in the following logical manner for easy and quick ways of learning complex concepts. In Chapters 1, 2, and 3, we discuss basic computer system architecture and essential operating systems concepts for implementing reliable and efficient C code. Then, you will go through C programming essential skills such as handling arrays, strings, unions, pointers, and memory management using open-source Linux tools (gcc, gdb, gcov, valgrind). In Chapters 4 and 5, you will be dedicatedly practicing runtime error handling and best practices in terms of Pointers usages, dynamic memory allocation handling, and accessing arrays, structures, strings, and buffers. Later you will learn the importance of these concepts while implementing system and network programming. Later in Chapters 6 and 7, you will explore the power of C programming in terms of system programming and high-performance computing; specifically, you will learn process and thread management for multitasking or multiprocessing through essential system calls. Mainly, you will learn programmer responsibilities in terms of process management tasks such as creating multiple processes, management of process segments, waiting for processes, termination activities, inter-process communication,

xx synchronization issues, and handling exceptional conditions. These are necessary skills for handling external inputs and runtime errors and offering reliable deployment opportunities for running C applications with multiple processes or threads. Next, in Chapters 8 and 9, you will explore the power of C socket programming and important system calls to implement TCP/UDP network applications. You will start with a quick introduction of the TCP/IP stack and applications. Specifically, you will learn flexible and error-free ways for handling socket buffers, packets, and fields accessed through C dynamic memory, strings, and pointers concepts. Moreover, we will also discuss essential programming ways (blocking and non-blocking), essential socket options for handling network server/client applications, runtime errors, and performance issues. Finally, in Chapter 10, you will learn Linux namespaces and their role in virtualization. Specifically, you will learn C programming ways and system calls for handling Linux namespaces and control groups. You will be experimenting with important Linux namespaces such as process, memory, and networking to learn how the popular lightweight virtualization solutions are working. This chapter will help you to explore the importance of virtualization in cloud environments. InTroduCTIon

1 © Dr Anil Kumar Rangisetti 2026 Dr A. K. Rangisetti, C Programming for System, Network, and Cloud Engineers, https://doi.org/10.1007/979-8-8688-1805-9_1 CHAPTER 1 Basic Computer System Architecture and Essential Operating System Concepts Learning about computer system architecture is essential for software developers to implement performance meeting optimized code for system software or applications. Mainly, insights into the underlying system architecture, its components (CPU, memory, cache, registers, I/O devices, system buses), and their interconnections are helpful to tune the application performance metrics such as throughput, latency, reliability, scalability, and security. For instance, knowing details of computer memory hierarchy and organization helps developers to implement suitable codes for minimizing memory access latencies and utilizing the memory optimally. Similarly, learning about the processor architecture in terms of the number of cores and their interconnection helps in writing suitable computational load distribution codes for maximizing CPU core utilization and minimizing communication latencies. On the other hand, an important system software called operating system (OS) runs over a computer system for simplifying its usage by end users and managing the system’s computational, memory, and input/output (IO) resources. OS helps software developers to a greater extent for developing applications and software-specific development tasks without worrying about the underlying system architecture. However, developers must know OS powers, responsibilities, and how to interact with the OS to develop secure and performance-optimized code. For instance, ignoring how the OS is handling a program execution and managing its system memory can lead to access violations and security

2 loopholes in software. In this book, we use Linux OS as a platform for practicing C programming. We discuss necessary Linux OS concepts to help developers to perform their programming activities. In addition to computer system architecture and OS, system developers must know how to utilize the system software tools such as compilers, debuggers, loaders, and linkers to simplify the software development, debugging, and deployment activities. In this chapter, we discuss the following topics to help C programmers learn and develop C applications and handle performance issues: • Introduction to basic computer system architecture • Operating system responsibilities • Importance of compiler, linker, and loader • Runtime environment of a process • C Programmer powers and responsibilities Basic Computer System Architecture The heart of any computer system is its central processing unit (CPU). It is interconnected with other important components to process software application inputs, perform computations, and store results. Chapter 1 BasiC Computer system arChiteCture and essential operating system ConCepts

3 Figure 1-1. Today’s general CPU architecture and its internal components Let’s inspect the details of today’s standard CPU architecture. From Figure 1-1, check the major components of a CPU architecture. CPU Architecture Today’s CPU has the following important components: • Multiple CPU cores with internal caches (L1, L2, and L3) • Floating point unit (FPU) • Memory management unit (MMU) • System buses for interconnecting memory and input/output (IO) devices Let’s check these internal component details for better programming. The CPU Cores: Today’s CPU is equipped with multiple CPU cores (refer to Figure 1-1), and each CPU core can support multiple hardware threads to improve the system processing power in terms of performing the parallel tasks. Most of the modern CPUs, such as Intel’s CPU support two hardware-level threads per core through hyper- Chapter 1 BasiC Computer system arChiteCture and essential operating system ConCepts