Linux 运行命令时修改.bashrc并结束命令时恢复原样

问题来源

我有一个bash程序，想要在执行该程序的时候修.bashrc，然后更新一些环境变量，并在结束(ctrl+c)的时候再把程序恢复原样。操作如下：

1. echo 命令把想要增加的内容写入.bashrc
2. 执行一些功能
3. 用trap 命令获取是否结束的操作
4. 备份.bashrc 为 bashrc_bak
5. 用sed '/搜索内容/d' bashrc_bak > .bashrc

例子, 下面的例子是我设置代理的脚本，执行该脚本的时候会在.bashrc中增加http_proxy和https_proxy的设置，关掉脚本后，删除之前增加的内容，并把http_proxy和https_proxy取消设置。

cp ~/.bashrc ./bashrc_bak   ## back bashrc file
echo "###proxy" >> ~/.bashrc
echo "export http_proxy=http://127.0.0.1:7890" >> ~/.bashrc
echo "export https_proxy=http://127.0.0.1:7890" >> ~/.bashrc
source ~/.bashrc

trap 'recover_bashrc' EXIT   ## trap exit (ctrl+c) signal then run recover_bashrc function

recover_bashrc()
{
    sed -i '/http_proxy=http/d' ~/.bashrc
    sed -i '/https_proxy=http/d' ~/.bashrc
    sed -i '/###proxy/d' ~/.bashrc
    echo "unset http_proxy" >> ~/.bashrc
    echo "unset https_proxy" >> ~/.bashrc
    source ~/.bashrc
    sed -i '/unset http_proxy/d' ~/.bashrc
    sed -i '/unset https_proxy/d' ~/.bashrc
}
./clash-linux-amd64 -d ./