System Calls for File Operations

Abstract

This chapter covers system calls for file operations. It explains the role of system calls and the online manual pages of Linux. It shows how to use system calls for file operations. It lists and explains the most commonly used system calls for file operations. It explains hard link and symbolic link files. It explains the stat system call in detail. Based on the stat information, it develops a ls-like program to display directory contents and file information. Next, it explains the open-close-lseek system calls and file descriptors. Then it shows how to use read-write system calls to read-write file contents. Based on these, it shows how to use system calls to display and copy files. It shows how to develop a selective file copying program which behaves like a simplified dd utility program of Linux. The programming project is to use Linux system calls to implement a C program, which recursively copies a directory to a destination. The purpose of the project is for the reader to practice the design of hierarchical program structures and use stat(), open(), read(), write() system calls for file operations.