int cd_GetUserData(UBYTE *filenm,int uindex,struct ud_Data *buffer);
   
   ---
   
   Purpose: gets user data of user with index 'uindex'.
   
   Results: user data in 'buffer' if found + sets return code to:
            
                    OK           - all ok
                    EFILE_OPEN   - file open error
                    EFILE_SEEK   - file seek error
                    EFILE_READ   - file read error
                    
      
   Usage  : rc = cd_GetUserData("User.data",index,&userdata);
            if(rc != OK)
            {
                /* error */
            }