-//
-// ----------- Writes the common part
-//
- fwrite ( &group,(size_t)2 ,(size_t)1 ,fp); //group
- fwrite ( &el, (size_t)2 ,(size_t)1 ,fp); //element
+ //
+ // ----------- Writes the common part
+ //
+ fp->write ((char*) &group,(size_t)2 ); //group
+ fp->write ( (char*)&el, (size_t)2 ); //element