问题描述
在什么情况下外壳环境会传递给子外壳?
Under what circumstances is the environment of the shell passed to the sub-shell?
推荐答案
子外壳程序始终从父外壳程序中获取所有变量.
A subshell always gets all variables from the parent shell.
man bash 将描述使用子shell的所有情况，主要是:命令& 命令|命令和(命令)
man bash will describe all the circumstances in which a subshell is used, which are mainly:command &command | command and( command )
所谓的环境仅包含环境变量( export变量)，并传递给每个子进程.即使调用 bash -c命令，它也不是子shell，而是全新的bash实例.
The so called environment only includes environment variables (export variable), and is passed on to every sub-process. Even when invoking bash -c command, which is not a sub-shell but a completely new bash instance.
在两种情况下，更改后的值都不会传递回父进程.
In both cases changed values are not passed back to the parent process.
这篇关于子外壳何时会继承其父外壳环境?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！