Tizen Developers

There is no difference public method with "extern" or not.

basically every default functions are extern function, so you don't write extern before the public method.

but if you want call some C++ function in C, use extern "C" for it.

// static_lib.h
class Foobar {
 public:
  Foobar() : mValue(321) {};
  int AddNumbers(int a);
 private:
  int mValue;
};


// static_lib_c.h
int asdf(int a);


// static_lib.cc
int Foobar::AddNumbers(int a) {
  return this->mValue + a;
}

static int static_a = 123;
extern "C" int asdf(int a) {
  return static_a + a;
}

// static_lib_test.cc
#include <static_lib.h>                                                         
                                                                                
int main() {                                                                    
  Foobar f;                                                                     
  int x = f.AddNumbers(123);                                                    
  printf("%d", x);                                                              
}                                                                               


// static_lib_test.c
#include <stdio.h>                                                              
                                                                                
#include <static_lib_c.h>                                                       
                                                                                
int main() {                                                                    
    printf("%d", asdf(321));                                                    
    return 0;                                                                   
}