Cross platform filesystem parsing without c++17 filesystem library [closed]

Any suggestions on writing cross platform code for parsing a directory recursively and obtaining a vector of filename (or foldername) with its type (file or folder)?

I don't have the option of using FileSystem from c++17 as i am on c++11 standard projects only. I am looking for any pointers on what approach could work for a solution which works both for Windows and Unix.

I am not looking for code but any relevant pointers are welcome which enable me to write common c++ code for windows and unix.