Filesystem Library

reading

See the cppreference.com page on filesystem

C++17 introduced the filesystem library to deal with paths and file operations.

By creating a path object, full paths to files can be built up using / as an operator, just like we would do on the commandline:

Listing 69 paths.cpp

#include <iostream>
#include <filesystem>

int main() {

    std::filesystem::path home("/home/zingale");

    auto full_path = home / "hello.cpp";

    std::cout << full_path << std::endl;

}

Here’s an example of looking at the path and different parts of a filename:

Listing 70 filesystem_example.cpp

#include <iostream>
#include <filesystem>

int main() {

    std::filesystem::path source{"./filesystem_example.cpp"};

    std::cout << source << std::endl;

    std::cout << std::filesystem::exists(source) << std::endl;

    std::cout << source.filename() << std::endl;
    std::cout << source.stem() << std::endl;
    std::cout << source.extension() << std::endl;

    std::cout << std::filesystem::current_path() << std::endl;
    std::cout << std::filesystem::absolute(source) << std::endl;
    std::cout << std::filesystem::canonical(source) << std::endl;
    std::cout << source.root_path() << std::endl;
}