//

// 8.1.filesystem.cpp

// chapter 08 filesystem

// modern c++ tutorial

//

// created by changkun at changkun.de

// https://github.com/changkun/modern-cpp-tutorial

//

#include <filesystem>

#include <fstream>

#include <iostream>

namespace fs = std::filesystem;

int main() {

// Work in a private scratch directory so the example is

// self-contained and repeatable.

const fs::path base = fs::temp_directory_path() / "modern-cpp-fs-demo";

fs::remove_all(base); // clean up any previous run

fs::create_directories(base / "sub"); // creates intermediate dirs

// Create a file.

std::ofstream(base / "hello.txt") << "hello, filesystem";

// Path decomposition (no filesystem access required).

const fs::path p = base / "hello.txt";

std::cout << "filename: " << p.filename() << "\n";

std::cout << "stem: " << p.stem() << "\n";

std::cout << "extension: " << p.extension() << "\n";

std::cout << "parent: " << p.parent_path() << "\n";

// Query the file.

std::cout << "exists: " << fs::exists(p) << "\n";

std::cout << "is_regular_file: " << fs::is_regular_file(p) << "\n";

std::cout << "file_size: " << fs::file_size(p) << "\n";

// Recursively iterate the directory tree.

std::cout << "entries:\n";

for (const auto& entry : fs::recursive_directory_iterator(base))

std::cout << " " << entry.path() << "\n";

// Copy, then rename.

fs::copy_file(p, base / "copy.txt");

fs::rename(base / "copy.txt", base / "renamed.txt");

std::cout << "renamed exists: " << fs::exists(base / "renamed.txt") << "\n";

// Clean up.

fs::remove_all(base);

std::cout << "after cleanup, exists: " << fs::exists(base) << "\n";

}