Mixing c++ string with c

Question

I have a c and cpp file

mycpp.cpp

fun()
{
//code goes here....
}

mycpp.h

#include<string>
struct str{
std::string a;
};
func();

myc.c

#include "mycpp.h"

func();
//with other c codes..

This is a part of large code list. So it gets compiled via c++ and c. My problem is when mycpp.h is compiled through myc.c (which is included in myc.c) , Compiler throws an error saying fatal error: string: No such file or directory

Is there some wrapper mechanism to overcome this scenario?

Check [this](http://stackoverflow.com/a/16058799/4790490), it might help. — Hardik Pithva, Apr 28 '16 at 07:38
You're including C++ constructs in C, what do you expect? They're different languages, of course it doesn't work. — Leandros, Apr 28 '16 at 07:41
You cannot mix 2 languages. You can compile C with standard c++ compilers such as g++ but not vice-versa. — Scaraux, Apr 28 '16 at 07:43
Would be helpful, if you could show us, why you included mycpp.h in the first place. — MikeMB, Apr 28 '16 at 07:43

Leandros · Answer 1 · 2016-04-28T07:49:27.973

You cannot include a C++ header file in a C file.

Declare the function func() with C linkage, and refer to it as an extern function inside your C file.

Example:

mycpp.cpp

void func(void)
{
    /* foo */
}

mycpp.h

extern "C" void func(void);

myc.c

extern void func(void);

/* you can now safely call `func()` */

You cannot use std::string in C, if you want to access your string, you have to pass it accordingly into your C code, by passing it a char const* with the contents of the string. You can get access to this string by calling std::string::c_str(). You can read more about c_str() here.

Mixing c++ string with c

1 Answers1