C++/Filesystem 文件类型

#include <iostream>
#include <filesystem>
#include <string>
namespace fs = std::filesystem;
void demo_status(const fs::path& p, fs::file_status s)
{
    std::cout << p;
    switch (s.type()) {
    case fs::file_type::none:
        std::cout << " has `not-evaluated-yet` type";
        break;
    case fs::file_type::not_found:
        std::cout << " does not exist";
        break;
    case fs::file_type::regular:
        std::cout << " is a regular file";
        break;
    case fs::file_type::directory:
        std::cout << " is a directory";
        break;
    case fs::file_type::symlink:
        std::cout << " is a symlink";
        break;
    case fs::file_type::block:
        std::cout << " is a block device";
        break;
    case fs::file_type::character:
        std::cout << " is a character device";
        break;
    case fs::file_type::fifo:
        std::cout << " is a named IPC pipe";
        break;
    case fs::file_type::socket:
        std::cout << " is a named IPC socket";
        break;
    case fs::file_type::unknown:
        std::cout << " has `unknown` type";
        break;
    default:
        std::cout << " has `implementation-defined` type";
        break;
    }
    std::cout << '\n';
}

void demo_perms(fs::perms p)
{
    using fs::perms;
    auto show = [=](char op, perms perm) {
        std::cout << (perms::none == (perm & p) ? '-' : op);
    };

    show('r', perms::owner_read);
    show('w', perms::owner_write);
    show('x', perms::owner_exec);
    show('r', perms::group_read);
    show('w', perms::group_write);
    show('x', perms::group_exec);
    show('r', perms::others_read);
    show('w', perms::others_write);
    show('x', perms::others_exec);
    std::cout << '\n';
}

int main()
{
    const std::string path{ "../../../testdata/list.txt" };


    demo_status(path, fs::status(path));

    // 2. permissions
    demo_perms(fs::status(path).permissions()); // rwxrwxrwx

    return 0;
}