C / C++ / MFC

EliottA wrote:

right now, I'm just trying to code a dog.

Comp_Users wrote:

I have an .cpp file which contains a set of utility functions like TrimMyString() etc which could be called a lot of times.

Comp_Users wrote:

I just have the global function body in the .cpp file and including this file in places where I am calling it.

1>XMLLoader.obj : error LNK2005: "void __cdecl TrimString(wchar_t *)" (?TrimString@@YAXPA_W@Z) already defined in UtilityFunctions.obj

1>Output/Sample.dll : fatal error LNK1169: one or more multiply defined symbols found

Comp_Users wrote:

I just have the global function body in the .cpp file and including this file in places where I am calling it.

Comp_Users wrote:

Could you please tell me as to what is causing this to happen?

#if !defined(ABC123)
#define ABC123
 
#pragma once
 
int TrimMyString();
int PaintMyHouse();
int SellMyStock();
 
#endif

// TrimMyString.h
extern CString TrimMyString (CString s);    // this will be included everywhere you need it. Note the extern.

// TrimMyString.cpp
#include "stdafx.h"  // I assume you're using VC++, in which you'll likely need this
#include "TrimMyString.h"

CString TrimMyString (CString s)
{
   do stuff with the string...
   return s;
}

// somefile.cpp
#include "stdafx.h"  // I assume you're using VC++, in which you'll likely need this
#include <some.h>
#include "Other.h"
#include "TrimMyString.h"  // <-- the important one!

BOOL SomeFunction ()
{
   s = "    Hello   ";
   s = TrimMyString (s);
   return TRUE;
}
</some.h>