Linking and Includes

[lTachyon]

Hi !

I have read some guides to understand what should I put in source files(cpp/c) and what in header files(h) (like http://www.cplusplus.com/forum/articles/10627/).

Some things I got from this guides is I should declare the functions headers in headers, to guard them, to don't include source files, etc.

So, I tried to do something like this:

emeralds.cpp

#include "emeralds.h"

int _tmain(int argc, _TCHAR* argv[])
{
	readConfig();

	return 0;
}

emeralds.h

#ifndef _EMERALDS_

#define _EMERALDS_

#include "configReader.h"

#endif 

configReader.cpp

#include "configReader.h"

bool readConfig()
{
//some function
}

configReader.h

#ifndef _CONFIG_READER_

#define _CONFIG_READER_

#include <SDKDDKVer.h>
#include <tchar.h>

struct config
{
//some struct
} serverConfig;

bool readConfig();

#endif 

I tried to compile this in VS2013. I disabled precompiled header(shouldn't I ?).

I got these errors:

Error	1	error LNK2005: "struct config serverConfig" (?serverConfig@@3Uconfig@@A) already defined in configReader.obj	D:\Info\cvis\emeralds\emeralds\emeralds.obj	emeralds
Error	2	error LNK1169: one or more multiply defined symbols found	D:\Info\cvis\emeralds\Debug\emeralds.exe	1	1	emeralds

I searched and I found that means I defined some things twice, but I don't know where .. :( How can I solve these problems ?

Am I right about what should I write in headers and source files ?

[rafae11]

on your header file i would remove serverConfig.

just have a struct as

struct config
{
//some struct
};

if you want to use the struct just instantiate it.

config serverConfig;