bash 在 cat 命令中转义 Unix 中的美元符号
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/21984960/
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
Escaping a dollar sign in Unix inside the cat command
提问by Iron Pillow
On Ubuntu, I would like to end up with a disk file that reads:
在 Ubuntu 上，我想最终得到一个磁盘文件，内容如下：
foo $(bar)
I would like to create this file using the catcommand, e.g.
我想使用cat命令创建这个文件，例如
cat <<EOF > baz.txt
type_magic_incantation_here_that_will_produce_foo_$(bar)
EOF
The problem is the dollar sign. I have tried multiple combinations of backslash, single-quote, and double-quote characters, and cannot get it to work.
问题是美元符号。我尝试了反斜杠、单引号和双引号字符的多种组合，但无法正常工作。
回答by tripleee
You can use regular quoting operators in a here document:
您可以在此处的文档中使用常规引用运算符：
$ cat <<HERE
> foo $(bar)
> HERE
foo $(bar)
or you can disable expansion in the entire here document by quoting or escaping the here-doc delimiter:
或者您可以通过引用或转义 here-doc 分隔符来禁用整个 here 文档中的扩展：
$ cat <<'HERE' # note single quotes
> foo $(bar)
> HERE
foo $(bar)
It doesn't matter whether you use single or double quotes or a backslash escape (<<\HERE); they all have the same effect.
使用单引号还是双引号或反斜杠转义符 ( <<\HERE)都没有关系；它们都具有相同的效果。
回答by Vinay
Backslash ('\') works for me. I tried it and here is the output:
反斜杠（'\'）对我有用。我试过了，这是输出：
$ cat <<EOF > tmp.txt
foo $(abc)
EOF
$ cat tmp.txt
foo $(abc)
I tried it on bash. I'm not sure whether you have to use a different escape character in a different shell.
我在 bash 上试过了。我不确定您是否必须在不同的 shell 中使用不同的转义字符。
