include header file - Printable Version

include header file - Printable Version

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include header file - mpo - 07-20-2007

I have included an header file (and two global variables) into vamosworld.h to control a virtual reality helmet.

Code:
#ifndef _VAMOSWORLD_H

using namespace std;

#include "font.h"

.....

#include "ai.h"

#include "trackmap.h"

#include "isense.h"  // Virtual Reality Helmet

//Virtual Reality Helmet variable

ISD_TRACKER_HANDLE trackerHandle; 

ISD_TRACKER_DATA_TYPE   trackerData; 

.....

I need to use these variables and some functions of the helmet into the files vamosworld.cpp and gui.cpp.
When i try to compile, the compiler don't tell me nothing but the linker give to me a lot of errors like:
"multiple definition of trackerHandle" or "multiple definition of trackerData" (the variables that i have defined).
"undefined references to ISD_OpenTracker" (a function of the helmet library).
Why if i have made the definitions into the #ifndef _VAMOSWORLD_H and vamosworld.h is included into vamosworld.cpp and gui.cpp ?
Down here there's a screenshot of a part of the errors:
http://vdrift.net/Gallery/media.php?f=0&sort=0&s=2007072002141515

- joevenzon - 07-20-2007

Why not put your globals in a C file instead of the header? You can access your globals from other C files using the extern keyword.