bash 如何使用grep查找仅包含小写的行
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How to find lines that contain ONLY lowercase using grep
提问by Roosh
I am new to bash and am learning to use grep.
我是 bash 新手，正在学习使用 grep。
grep ^[a-z] file.txtwill show all the lines that begin with lowercasegrep [a-z] file.txtall lines with lowercase
grep ^[a-z] file.txt将显示所有以小写开头的行grep [a-z] file.txt所有以小写开头的行
Can't figure out how to show lines with ALL lowercase, can anyone help?
无法弄清楚如何用所有小写字母显示行，有人可以帮忙吗？
回答by anubhava
You can use anchors in your regex for egrep:
您可以在正则表达式中使用锚点egrep：
egrep '^[[:lower:]]+$' file
This egrepwill only find lines that have only lowercase lettersin the (not even space is allowed).
这egrep只会找到只有小写字母的行（甚至不允许空格）。
回答by Unknown
This will match and exclude lines that contain something else besides a-z.
这将匹配并排除包含除 之外的其他内容的行a-z。
cat file.txt | grep -v '[^[:lower:]]'
If you need to allow symbols too (this example allows !, +, ,):
如果您也需要允许符号（此示例允许!, +, ,）：
cat file.txt | grep -v '[^[:lower:]!+,]'
