shell编程中的PATH路径问题

shell编程中的PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:~/bin。
1、这个是不是可有可无的,有什么作用?
2、这个是固定的还是根据自己的linux环境中的echo $PATH而定?
我是菜鸟,请大神指导,多谢。

2个回答

一般默认,但你可以指定!

使用export PATH=的方式

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