When output is created from multiple files or the standard input stream, the current date and time are used instead of the filename and creation date.
当从多个文件或标准输入流创建输出时，可以使用当前日期和时间替换文件名和创建日期。
2
Since a compensation service has an associated, unchangeable input message at the time it is run, its output message can never be used, for example, as input to another compensation service.
We know how many people are coming to eat, we know how much inventory is consumed, but the owner does not numerically associate the inventory input to the output over time.