Linux 如何在 Bash/Grep 中转义单引号？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/7254509/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How to escape single quotes in Bash/Grep?
提问by JohnnyFromBF
I want to search with grep for a string that looks like this:
我想用 grep 搜索如下所示的字符串：
something ~* 'bla'
I tried this, but the shell removes the single quotes argh..
我试过这个，但是shell删除了单引号argh ..
grep -i '"something ~* '[:alnum:]'"' /var/log/syslog
What would be the correct search?
什么是正确的搜索？
采纳答案by eckes
grep -i "something ~\* '[[:alnum:]]*'" /var/log/syslog
works for me.
为我工作。
- escape the first
*to match a literal*instead of making it the zero-or-more-matches character:~*would match zero or more occurrences of~while~\*matches the expression~*aftersomething - use double brackets around
:alnum:(see example here) - use a
*after[[:alnum::]]to match not only onecharacter between your single quotes but several of them - the single quotes don't have to be escaped at all because they are contained in an expression that is limited by double quotes.
- 转义第一个
*匹配文字*而不是使其成为零个或多个匹配字符：~*将匹配零次或多次出现的~while~\*匹配~*后面的表达式something - 在周围使用双括号
:alnum:（请参阅此处的示例） - 使用
*after[[:alnum::]]不仅可以匹配单引号之间的一个字符，还可以匹配其中的几个字符 - 单引号根本不必转义，因为它们包含在受双引号限制的表达式中。
回答by Matteo
- character classes are specified with
[[:alnum:]](two brackets) [[:alnum:]]is matching only onecharacter. To match zero or more characters[[:alnum:]]*you can just use
" "to quote the regex:grep -i "something ~\* '[[:alnum:]]*'" /var/log/syslog
- 字符类用
[[:alnum:]]（两个括号）指定 [[:alnum:]]只匹配一个字符。匹配零个或多个字符[[:alnum:]]*您可以使用
" "引用正则表达式：grep -i "something ~\* '[[:alnum:]]*'" /var/log/syslog
Matteo
马泰奥
回答by Diego Sevilla
It seems as per your expression, that you are using first ', then ". If you want to escape the single quotes, you can either use 'and escape them, or use double quotes. Also, as Matteo comments, character classes have double square brackets Either:
根据您的表达，您似乎先使用'，然后使用"。如果要转义单引号，可以使用'并转义它们，也可以使用双引号。此外，正如 Matteo 所评论的，字符类有两个方括号或者：
grep -i "something \~\* '[[:alnum:]]+'" /var/log/syslog
or
或者
grep -i 'something ~* \'[[:alnum:]]+\'' /var/log/syslog
回答by ghoti
If you doneed to look for quotes in quotes in quotes, there are ugly constructs that will do it.
如果您确实需要在引号中的引号中查找引号，那么有一些丑陋的构造可以做到这一点。
echo 'And I said, "he said WHAT?"'
works as expected, but for another level of nesting, the following doesn't workas expected:
按预期工作，但对于另一个级别的嵌套，以下内容无法按预期工作：
echo 'She said, "And I said, \'he said WHAT?\'"'
Instead, you need to escape the inner single quotes outsidethe single-quoted string:
相反，您需要转义单引号字符串之外的内部单引号：
echo 'She said, "And I said, '\''he said WHAT?'\''"'
Or, if you prefer:
或者，如果您更喜欢：
echo 'She said, "And I said, '"'"'he said WHAT?'"'"'"'
It ain't pretty, but it works. :)
它不漂亮，但它有效。:)
Of course, all this is moot if you put things in variables.
当然，如果你把东西放在变量中，所有这些都是没有意义的。
[ghoti@pc ~]$ i_said="he said WHAT?"
[ghoti@pc ~]$ she_said="And I said, '$i_said'"
[ghoti@pc ~]$ printf 'She said: "%s"\n' "$she_said"
She said: "And I said, 'he said WHAT?'"
[ghoti@pc ~]$
:-)
:-)
