Bash：添加磁盤到fstab的腳本（如果不存在）

Question

首先，我已經閱讀了很多文章（請參閱底部）if-clause在文件中搜索特定的字符串並遵循這些職位1to1，但是我不要設法讓我的腳本工作。我想在/etc/fstab一個條目，如果不存在的：在您的幫助提前

#!/bin/bash 
fstab=/etc/fstab 

if grep -q "poky-disc" "$fstab" 
then 
    echo "#poky-disc" >> /etc/fstab 
    echo "/dev/sdb1 /media/poky ext4 defaults 0 2" >> /etc/fstab 
else 
    echo "Entry in fstab exists." 
fi 

感謝。這些都是類似的帖子，這沒有幫助我進一步：

• How to test if string exists in file with Bash shell?
• How to check if a file contains a specific string using bash

Answer 1

#!/bin/bash 
fstab=/etc/fstab 

if [[ $(grep -q "poky-disc" "$fstab") ]] 
# forgiving me for being a bit of over-rigorous, you might want to change this matching word, as below, 'poky-disc' merely a comment, not exactly a config line, so 
then 
    echo "#poky-disc" >> /etc/fstab 
    echo "/dev/sdb1 /media/poky ext4 defaults 0 2" >> /etc/fstab 
else 
    echo "Entry in fstab exists." 
fi