linux - 不能在 bash if 语句中使用 'sudo'

Question

我有双 linux 引导我是 bash 的新手

运行以下脚本时出现奇怪的错误:

if [[ 'grep -i fedora /etc/issue' ]]; then
        echo "the OS is Fedora"
        $(sudo yum update -y && sudo yum upgrade -y)
else
        echo "the OS is Ubuntu"
        $(sudo apt-get update && sudo apt-get upgrade -y && sudo apt-get dist-upgrade -y)
fi

error : ./server_update.sh: line 9: Loaded: command not found

Answer 1

它正在尝试执行您的 apt-get/yum 命令的输出，丢失 $(..)

你一开始也有问题:

if [[ -n "$(grep -i fedora /etc/issue)" ]]; then

是检查字符串是否存在的正确方法。

您的代码应该如下所示:

if [[ -n "$(grep -i fedora /etc/issue)" ]]; then
    echo "the OS is Fedora"
    sudo yum update -y && sudo yum upgrade -y
else
    echo "the OS is Ubuntu"
    sudo apt-get update && sudo apt-get upgrade -y && sudo apt-get dist-upgrade -y
fi