Book Image

CentOS Quick Start Guide

By : Shiwang Kalkhanda
Book Image

CentOS Quick Start Guide

By: Shiwang Kalkhanda

Overview of this book

Linux kernel development has been the worlds largest collaborative project to date. With this practical guide, you will learn Linux through one of its most popular and stable distributions. This book will introduce you to essential Linux skills using CentOS 7. It describes how a Linux system is organized, and will introduce you to key command-line concepts you can practice on your own. It will guide you in performing basic system administration tasks and day-to-day operations in a Linux environment. You will learn core system administration skills for managing a system running CentOS 7 or a similar operating system, such as RHEL 7, Scientific Linux, and Oracle Linux. You will be able to perform installation, establish network connectivity and user and process management, modify file permissions, manage text files using the command line, and implement basic security administration after covering this book. By the end of this book, you will have a solid understanding of working with Linux using the command line.
Table of Contents (11 chapters)

Special permissions

Besides the basic permissions set, which is applicable by default, Linux also has some special/advanced permission sets, which are used sometimes to enhance some functionalities. These permissions are applicable to files (mainly executable files) and directories. These are setuid, setgid, and sticky bit.

Modifying special permissions for files

Setuid and setgid are two special permissions that are applied to executable files.

If setuid is applied to an executable file, it means that if that file is executed as a program, then it will run as the user of the file and not as the user who ran the program.

Similarly, when setgid is applied to the file, it runs as the group of the file and not as the group that...