读取包含字符串的行（Bash）
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Read line containing String (Bash)
提问by Omnomnom
I have a file, and its something like this:
我有一个文件，它是这样的：
Device: name1
random text
Device: name2
random text
Device: name3
random text
I have a variable: MainComputer
我有一个变量：MainComputer
What I want to get (for each name, i have like 40 names):
我想得到什么（对于每个名字，我有 40 个名字）：
MainComputer -> name1
MainComputer -> name2
MainComputer -> name3
What I have:
我拥有的：
var="MainComputer"
var1=$(awk '/Device/ {print }' file)
echo "$var -> $var1"
This only gives the arrow "->" and the link for the first variable, I want them for the other 40 variables...
这仅提供箭头“->”和第一个变量的链接，我希望它们用于其他 40 个变量......
Thanks anyway!
不管怎么说，还是要谢谢你！
回答by fedorqui 'SO stop harming'
Let me present you awk:
让我向您介绍awk：
$ awk '/Device/ {print }' file
name1
name2
name3
This prints the second field on the lines containing Device. If you want to check that they start with Device, you can use ^Device:.
这将在包含 的行上打印第二个字段Device。如果要检查它们是否以 Device 开头，可以使用^Device:.
Update
更新
To get the output you mention in your edited question, use this:
要获得您在编辑的问题中提到的输出，请使用以下命令：
$ awk -v var="MainComputer" '/Device/ {print var, "->", }' a
MainComputer -> name1
MainComputer -> name2
MainComputer -> name3
It provides the variable name through -vand then prints the line.
它通过提供变量名称-v，然后打印该行。
Find some comments regarding your script:
查找有关您的脚本的一些评论：
file="/scripts/file.txt"
while read -r line
do
if [$variable="Device"]; then # where does $variable come from? also, if condition needs tuning
device='echo "$line"' #to run a command you need `var=$(command)`
echo $device #this should be enough
fi
done <file.txt #why file.txt if you already stored it in $file?
Check bash string equalityto see how [[ "$variable" = "Device" ]]should be the syntax (or similar).
检查bash 字符串相等性以查看[[ "$variable" = "Device" ]]语法（或类似语法）应该如何。
Also, you could say while read -r name value, so that $valuewould contain from the 2nd value on.
此外，您可以说while read -r name value, 以便$value从第二个值开始包含。
回答by Daniel Stenberg
Alternatively, let me present you grep and cut:
或者，让我向您展示 grep 和 cut：
$ grep "^Device:" $file | cut "-d " -f2-
