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#!/bin/bash
set -e
command 1
command 2
...
exit 0
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Every script you write should include set -e at the top. This tells bash that it should exit the script if any statement returns a non-true return value. The benefit of using -e is that it prevents errors snowballing into serIoUs issues when they Could have been caught earlier. Again,for readability you may want to use set -o errexit.
你写的每个脚本都应该在文件开头加上set -e,这句语句告诉bash如果任何语句的执行结果不是true则应该退出。这样的好处是防止错误像滚雪球般变大导致一个致命的错误，而这些错误本应该在之前就被处理掉。如果要增加可读性，可以使用set -o errexit，它的作用与set -e相同。
Using -e gives you error checking for free. If you forget to check something,bash will do it for you. Unfortunately it means you can't check $? as bash will never get to the checking code if it isn't zero. There are other constructs you Could use:
使用-e帮助你检查错误。如果你忘记检查（执行语句的结果），bash会帮你执行。不幸的是，你将无法检查$?，因为如果执行的语句不是返回0，bash将无法执行到检查的代码。你可以使用其他的结构：
Could be replaced with
能够被代替为
copy
