code: public static synchronized SystemConfiguration createSystemConfiguration()
              throws IOException {
          if (self == null) {
              if (getenv(BELFRAMEWORK_HOME_ENV_VAR) == null) {
                  String err = MISSING_SYSCFG;
                  err = err.concat(": environment variable not set ");
                  err = err.concat(BELFRAMEWORK_HOME_ENV_VAR);
                  throw new IOException(err);
              }
              self = new SystemConfiguration();
          }
          return self;
      }
docs: Creates the system configuration as defined by the environment.
  
  @return {@link SystemConfiguration}
  @throws IOException Thrown if an I/O error occurs