Yes [0].

    extern (C++) int foo(int i, int j, int k);

In fact, D can both access C++, and C++ can access D, as you can see further down that link, on classes.

But, if you don't want C++, then [1]:

    extern (C) int foo(int i, int j, int k);

Which is actually in the article.

[0] http://dlang.org/spec/cpp_interface.html

[1] http://dlang.org/spec/interfaceToC.html

Yep, except you'd write it

    extern(C) { void foo(); }

https://dlang.org/spec/interfaceToC.html

Here is an example:

https://jugad2.blogspot.in/2016/09/calling-simple-c-function...