Book Image

C++17 STL Cookbook

By : Jacek Galowicz
Book Image

C++17 STL Cookbook

By: Jacek Galowicz

Overview of this book

C++ has come a long way and is in use in every area of the industry. Fast, efficient, and flexible, it is used to solve many problems. The upcoming version of C++ will see programmers change the way they code. If you want to grasp the practical usefulness of the C++17 STL in order to write smarter, fully portable code, then this book is for you. Beginning with new language features, this book will help you understand the language’s mechanics and library features, and offers insight into how they work. Unlike other books, ours takes an implementation-specific, problem-solution approach that will help you quickly overcome hurdles. You will learn the core STL concepts, such as containers, algorithms, utility classes, lambda expressions, iterators, and more, while working on practical real-world recipes. These recipes will help you get the most from the STL and show you how to program in a better way. By the end of the book, you will be up to date with the latest C++17 features and save time and effort while solving tasks elegantly using the STL.
Table of Contents (18 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Index

Implementing a tool that reduces folder size by substituting duplicates with symlinks


There are a lot of tools that compress data in various ways. The most famous examples for file packing algorithms/formats are ZIP and RAR. Such tools try to reduce the size of files by reducing internal redundancy.

Before compressing files in archives, a very simple way to reduce disk usage is just deletingduplicate files. In this recipe, we will implement a little tool that crawls a directory recursively. While crawling, it will look for files that have the same content. If it finds such files, it will remove all duplicates but one. All removed files will be substituted with symbolic links that point to the now unique file. This saves spaces without any compression, while at the same time preserving all data.

How to do it...

In this section, we will implement a little tool that finds out which files in a directory are duplicates of each other. With that knowledge, it will remove all but one of all duplicated...