c++ - Header for environ on Mac -

how find out header "environ" on mac? want include in project. thank you! https://developer.apple.com/library/mac/documentation/darwin/reference/manpages/man7/environ.7.html

there no header file; manage says need declare yourself:

#include <iostream>  extern char **environ;  int main() {     (unsigned = 0; environ[i]; i++)         std::cout << environ[i] << std::endl;     return 0; } 

you might better off sticking genenv() , setenv() unless need wholesale manipulation, example, before passing child process.