DevOps in Linux — System Call Introduction

Deep dive into Linux system

Note, full mind map is available at: “DevOps in Linux Mind Map”

In the context of Linux, a system call is a specific type of function that allows user-space programs to interact with the Linux kernel. Through system calls, software applications request the kernel to perform various operations like file I/O, process control, networking, and memory management, among others.

Below is the process flow of a simple open file system call:

Why Do We Need System Call?

System calls are essential for several reasons, mainly related to security, abstraction, and system integrity. Here are few main reasons:

Security

• Privilege Separation: Modern operating systems employ a security model that separates user space (where user programs run) from kernel space (where the OS runs). This prevents user programs from directly accessing hardware or critical system resources, which could otherwise be a huge security risk.
• Permission Checks: When a system call is made, the kernel can…