Question

我编写了一个bash脚本，并通过read获取了一些用户输入。我想通过读取将变量放在cat << EOF >> file的文件中。我的问题是每个变量都得到“双重报价”。我该如何防止这种情况？

echo "Whats your name?"
read yourname

cat << EOF >> /path/to/file
Your Name is "${yourname}"

EOF

该文件的内容是：

Your Name is "djgudb"

应该是：

Your Name is djgudb

Answer 1

引号在heredocs中没有句法意义，所以如果你不希望它们是文字的话，不要把它们放在那里。

echo "Whats your name?"
read yourname

cat << EOF >> /path/to/file
Your Name is ${yourname}

EOF

Answer 2

bash手册说：

The format of here-documents is:

          [n]<<[-]word
                  here-document
          delimiter

   No  parameter  and variable expansion, command substitution, arithmetic
   expansion, or pathname expansion is performed on word.  If any part  of
   word  is  quoted, the delimiter is the result of quote removal on word,
   and the lines in the  here-document  are  not  expanded.   If  word  is
   unquoted,  all  lines  of  the here-document are subjected to parameter
   expansion, command substitution, and arithmetic expansion, the  charac‐
   ter  sequence  \<newline>  is  ignored, and \ must be used to quote the
   characters \, $, and `.

所以你需要

cat << EOF >> /path/to/file
Your Name is ${yourname}

EOF

在heredoc中使用shell变量的双引号

2 个答案: