filesystem/checkpath1.cpp

The following code example is taken from the book
C++17 - The Complete Guide by Nicolai M. Josuttis, Leanpub, 2017
The code is licensed under a Creative Commons Attribution 4.0 International License.

---

// raw code

#include <iostream>
#include <filesystem>
#include <cstdlib>    // for EXIT_FAILURE

int main(int argc, char* argv[])
{
  if (argc < 2) {
    std::cout << "Usage: " << argv[0] << " <path> \n";
    return EXIT_FAILURE;
  }

  std::filesystem::path p{argv[1]};  // p represents a filesystem path (might not exist)
  if (is_regular_file(p)) {          // is path p a regular file?
    std::cout << p << " exists with " << file_size(p) << " bytes\n";
  }
  else if (is_directory(p)) {        // is path p a directory?
    std::cout << p << " is a directory containing:\n";
    for (const auto& e : std::filesystem::directory_iterator{p}) {
      std::cout << "  " << e.path() << '\n';
    }
  }
  else if (exists(p)) {              // does path p actually exist?
    std::cout << p << " is a special file\n";
  }
  else {
    std::cout << "path " << p << " does not exist\n";
  }
}