def exec_or_exit(cmd)
      status = execute(cmd)
      if (status.to_i.nonzero?)
        error("The command '#{cmd}' failed with exit status #{status.to_i}")
      end
      status
    end
def exec_or_exit(cmd)
      status = execute(cmd)
      if (status.to_i.nonzero?)
        error("The command '#{cmd}' failed with exit status #{status.to_i}")
      end
      status
    end
execute_in_dir
 Execute a given command - exit if status != 0