Use Relative Paths with Directory Iterator

Yes, std::filesystem::directory_iterator can be used with relative paths. When using relative paths, they are resolved relative to the current working directory of the program.

Here’s an example using a relative path:

1#include <filesystem>
2#include <iostream>
3
4namespace fs = std::filesystem;
5
6int main() {
7  fs::path relative_path{"."};  Current directory
8  fs::directory_iterator start{relative_path};
9  fs::directory_iterator end{};
10
11  for (auto iter{start}; iter != end; ++iter) {
12    std::cout << iter->path().string() << '\n';
13  }
14}

1.\file1.txt
2.\file2.txt
3.\subdirectory

Steps to Use Relative Paths:

1. Specify Relative Path: Use a relative path (e.g., "." for the current directory or "../" for the parent directory).
2. Initialize Iterator: Create a std::filesystem::directory_iterator with the relative path.
3. Iterate and Process: Loop through the directory entries and process them as needed.

Combining with Absolute Paths:

You can combine relative paths with std::filesystem::absolute() to get the absolute path:

1#include <filesystem>
2#include <iostream>
3
4namespace fs = std::filesystem;
5
6int main() {
7  fs::path relative_path{"."};
8  fs::path absolute_path =
9    fs::absolute(relative_path);  
10
11  std::cout << "Absolute path: "
12    << absolute_path.string() << '\n';
13
14  fs::directory_iterator start{absolute_path};
15  fs::directory_iterator end{};
16
17  for (auto iter{start}; iter != end; ++iter) {
18    std::cout << iter->path().string() << '\n';
19  }
20}

1Absolute path: C:\current\working\directory
2C:\current\working\directory\file1.txt
3C:\current\working\directory\file2.txt
4C:\current\working\directory\subdirectory

Changing the Current Working Directory:

You can change the current working directory using std::filesystem::current_path():

1#include <filesystem>
2#include <iostream>
3
4namespace fs = std::filesystem;
5
6int main() {
7  fs::path new_cwd{R"(c:\test)"};
8  fs::current_path(new_cwd);  
9
10  // Current Directory
11  fs::directory_iterator start{"."};  
12  fs::directory_iterator end{};
13
14  for (auto iter{start}; iter != end; ++iter) {
15    std::cout << iter->path().string() << '\n';
16  }
17}

1.\file1.txt
2.\file2.txt
3.\subdirectory

Key Considerations:

• Path Resolution: Relative paths are resolved based on the current working directory.
• Portability: Be mindful of the current working directory, especially when running the program from different locations or environments.

Using std::filesystem::directory_iterator with relative paths is straightforward and provides flexibility in navigating and processing file systems relative to your program’s current working directory.