Checking the properties of an existing file or directory

The filesystem library provides functions and types that enable developers to check for the existence of a filesystem object, such as a file or directory, its properties, such as the type (the file, directory, symbolic link, and more), the last write time, permissions, and more. In this recipe, we will look at what these types and functions are and how they can be used.

Getting ready

For the following code samples, we will use the namespace alias fs for the std::filesystem namespace. The filesystem library is available in the header with the same name, <filesystem>. Also, we will use the variables shown here, path for the path of a file, and err for receiving potential operating system error codes from the filesystem APIs:

auto path = fs::current_path() / "main.cpp";
auto err = std::error_code{};

Also, the function to_time_t shown here will be referred to in this recipe:

  template <typename...