std::experimental::filesystem:: begin (directory_iterator) , std::experimental::filesystem:: end (directory_iterator)

From cppreference.com
C++
Filesystem library
Classes
Functions
File types
directory_iterator
directory_iterator begin ( directory_iterator iter ) ;
(1) (filesystem TS)
directory_iterator end ( const directory_iterator & ) ;
(2) (filesystem TS)
1) Returns iter unchanged.
2) Returns a default-constructed directory_iterator , which serves as the end iterator. The argument is ignored.

These non-member functions enable the use of directory_iterator s with range-based for loops.

Parameters

iter - a directory_iterator

Return value

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

Exceptions

noexcept specification:
noexcept

Example

Run this code 
#include <experimental/filesystem>
#include <fstream>
#include <iostream>
namespace fs = std::experimental::filesystem;
 
int main()
{
    fs::create_directories("sandbox/a/b");
    std::ofstream("sandbox/file1.txt");
    std::ofstream("sandbox/file2.txt");
    for (auto& p : fs::directory_iterator("sandbox"))
        std::cout << p << '\n';
    fs::remove_all("sandbox");
}

Possible output: 

"sandbox/a"
"sandbox/file1.txt"
"sandbox/file2.txt"

See also

range-based for loop support
(function)
Retrieved from " https://en.cppreference.com/mwiki/index.php?title=cpp/experimental/fs/directory_iterator/begin&oldid=154837 "