Writing and reading string class

It''s working perfectly fine for me.

$ cat foo.cc
#include <iostream>
#include <fstream>
#include <string>

int main()
{
   std::string a="test", b;
   std::ofstream outf("a.fl", std::ios::binary);
   std::ifstream inf("a.fl", std::ios::binary);

   outf<<a;
   outf.close();
   inf>>b;
   inf.close();

   std::cout << b << std::endl;
}

And don''t use [code‍] blocks if you''re not willing to replace your < with &lt;

I have noticed that when I read the string, I get the string and the string I wrote afterwards. I assume that writting a string in binary does not put ''\0''.
Therefore I need to put it explicitly.
My question is, does endl functions as ''\0''?

No. endl works as ''\n'', and >> reads whitespace-delimited words. Opening a file in ''binary mode'' doesn''t mean the data is read/written in binary, only that (platform-dependent) newline translation is not done.