Working with filesystem paths is always tedious if we don't have a library that helps us because there are many conditions that we need to handle.

Some paths are absolute, some are relative, and maybe they are not even straightforward because they also contain . (current directory) and .. (parent directory) indirections. Then, at the same time, different operating systems use the slash / to separate directories (Linux, MacOS, and different UNIX derivatives), or the backslash (Windows). And of course there are different types of files.

Since every other program that handles filesystem-related things needs such functionality, it is great to have the new filesystem library in the C++17 STL. The best thing about it is that it works the same way for different operating systems, so we don't have to write different code for versions of our programs that support different operating systems.

In this chapter, we will first see how the path class works, because it is most central to anything else in this library. Then, we will see how powerful but yet simple to use directory_iterator and recursive_directory_iterator classes are, while we do useful things with files. In the end, we will use some small and simple example tools that do some real-life tasks related to the filesystem. From this point, it will be easy to build more complex tools.