让我们探讨一下外部命令以及如何运行它们，以及如何判断某个命令是否是内部的。

Let's now look at external commands and how to run them, and how to tell if a command is internal.

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任意接下来的外部命令，如果他们是在默认的SYSTEM环境下运行，将把它们的输入定向到默认的FIFO(先入先出，first - in - first - out)。

Any subsequent external commands, if they are run in the default SYSTEM environment, will direct their output to the default FIFO. (first-in-first-out).

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周二晚的这次惨败的关键在于Selerity的自动计算机程序bots； bots是一种能执行外部命令的自动运行型木马，可以扫描网页搜寻有利可图的秘密信息。

The key factor in Tuesday evening's fiasco was that Selerity's automatic computer programs, called bots, which scan the web for juicy financial details, were able to find the mistake so quickly.

youdao

周二晚的这次惨败的关键在于Selerity的自动计算机程序bots； bots是一种能执行外部命令的自动运行型木马，可以扫描网页搜寻有利可图的秘密信息。

The key factor in Tuesday evening's fiasco was that Selerity's automatic computer programs, called bots, which scan the web for juicy financial details, were able to find the mistake so quickly.

youdao