Course 4 - Learning Linux Shell Scripting | Episode 3: Comprehensive Unix File and Directory Management Utilities

In this lesson, you’ll learn about: 📁 File Creation, Size, and Storage Management• Generating Files of Any Size: Learn to use the low-level dd command to create files of specific sizes using block size (BS) and count parameters—ideal for test data or loopback file systems.• Loopback File Systems: Understand how to create virtual disk images that can be mounted like physical drives using mount -o loop, and how to partition them with tools like fdisk.• Generating Blank Files in Bulk: Use touch to create empty files or modify timestamps, with examples of bulk file creation using shell patterns. ⚖️ Comparison, Difference, and Duplicate Handling• Intersection and Set Difference: Apply the comm command to find lines common to or unique between two sorted files.• Finding and Deleting Duplicates: Build scripts that detect duplicates by first comparing file sizes, then confirming identical content via checksums (md5sum), and finally deleting redundant copies.• File Differencing and Patching: Use diff -u to create readable patch files and apply or revert changes using patch and patch -R. 🔒 File Permissions and Security Attributes• Permissions and Ownership: Manage access rights using chmod (symbolic or numeric), and change ownership with chown.• Special Permissions: Understand Set UID, Set GID, and the Sticky Bit (+t), especially in shared directories like /tmp.• Immutability: Protect files from modification or deletion using chattr +i, even against superuser changes. 📊 File Information, Types, and Statistics• Symbolic Links: Create, find, and inspect symbolic links using ln, find, and readlink.• File Type Enumeration: Use the file command to detect file types and script recursive directory scans to count and categorize them.• Counting Data: Employ wc to count lines, words, characters, and determine the longest line length with -L. 📜 Viewing and Navigation Utilities• Viewing File Portions: Display specific sections of files with head and tail, and monitor live log updates using tail -f.• Directory Listing Alternatives: Filter output from ls -F or use find -type d to list only directories.• Fast Navigation: Use pushd and popd to manage a directory stack for quick path switching.• Visualizing Directory Structures: Generate a tree-style directory overview using the tree command, including pattern filtering and HTML output. This lesson provides practical mastery of Unix’s “everything is a file” philosophy—equipping you to create, compare, protect, and navigate files and directories with precision and efficiency.You can listen and download our episodes for free on more than 10 different platforms:https://linktr.ee/cybercode_academy