visual studio - Clear data inside all files in C++ -

hi guys programming on c++. wish clear data inside of files in current directory. can tell me command files?

that trying doesn't work:

ofs.open("*.*", ios::out | ios::trunc); 

the problem is: open("*.*",

fstream can't open files of directory, instead, can iterate each file.
example works on c++17

    #include <string>     #include <iostream>     #include <filesystem>     #include <fstream>     //namespace fs = std::experimental::filesystem; //for visual studio     namespace fs = std:::filesystem;     int main()     {         std::string path = "path_to_directory";         (auto & p : fs::directory_iterator(path)) {             if (fs::is_regular_file(p)){                 std::fstream fstr;                 fstr.open(p.path().c_str(), std::ios::out | std::ios::trunc);                 //do                 fstr.close()             }         }     } 

older compilers(windows):

#include <windows.h> #include <string> #include <fstream>   std::wstring path = l"path_to_directory";  path += l"\\*"; win32_find_data data; handle hfind; if ((hfind = findfirstfile(path.c_str(), &data)) != invalid_handle_value) {     {         if (data.dwfileattributes & file_attribute_archive) {             std::fstream fstr;             fstr.open(data.cfilename, std::ios::out | std::ios::trunc);             //do             fstr.close();         }     } while (findnextfile(hfind, &data) != 0);     findclose(hfind); }