std::filesystem:: begin (recursive_directory_iterator) , std::filesystem:: end (recursive_directory_iterator)

From cppreference.com
C++
Filesystem library
Classes
Functions
File types
std::filesystem::recursive_directory_iterator
Defined in header <filesystem>
recursive_directory_iterator begin ( recursive_directory_iterator iter ) noexcept ;
(1) (since C++17)
recursive_directory_iterator end ( recursive_directory_iterator ) noexcept ;
(2) (since C++17)
1) Returns iter unchanged.
2) Returns a default-constructed recursive_directory_iterator , which serves as the end iterator. The argument is ignored.

These non-member functions enable the use of recursive_directory_iterator s with range-based for loops and make recursive_directory_iterator a range type (since C++20) .

Parameters

iter - a recursive_directory_iterator

Return value

1) iter unchanged.
2) End iterator (default-constructed recursive_directory_iterator ).

Example

Run this code 
#include <cstdlib>
#include <filesystem>
#include <fstream>
#include <iostream>
namespace fs = std::filesystem;
 
int main()
{
    fs::current_path(fs::temp_directory_path());
    fs::create_directories("sandbox/a/b");
    std::ofstream("sandbox/file1.txt");
    fs::create_symlink("a", "sandbox/syma");
 
    std::cout << "Print dir structure using OS specific command 'tree':\n";
    std::system("tree --noreport sandbox");
 
    std::cout << "\nPrint dir structure using directory iterator:\n";
    for (auto& p : fs::recursive_directory_iterator("sandbox"))
        std::cout << p << '\n';
 
    fs::remove_all("sandbox");
}

Possible output: 

Print dir structure using OS specific command 'tree':
sandbox
├── a
│   └── b
├── file1.txt
└── syma -> a
 
Print dir structure using directory iterator:
"sandbox/syma"
"sandbox/file1.txt"
"sandbox/a"
"sandbox/a/b"

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 3480 C++17 end took the argument by reference takes the argument by value

See also

(C++17)
range-based for loop support
(function)
Retrieved from " https://en.cppreference.com/mwiki/index.php?title=cpp/filesystem/recursive_directory_iterator/begin&oldid=158510 "