function called from .cpp file which is defined in in .c file
===

In projectA.vcproj

fileA.h
--------

    #ifdef __cplusplus
    extern "C" {
    #endif
    void functionA();
    #ifdef __cplusplus
    }
    #endif

fileA.c
---------

    void functionA()
    {
    //function defined
    }

In projectB.vcproj:

fileB.h
---------

    void functionB() ;

fileB.cpp
------------
    #include "fileA.h"
    #include "fileB.h"
    void functionB() {
    	functionA(); // error: undefined reference to 'functionA'
    }

I am getting the error when I compile my code on Linux, please help me fix this. 
