雙引號

雙引號保留除 " 終結符,$ 擴充套件,`命令替換和任何這些字元的\轉義(以及換行符)之外的所有字元。請注意,除非後跟特殊字元,否則將保留文字\

一般轉義:

$ printf "\"quoted string\"\\n"
"quoted string"
$ printf "\`\`quoted string''\n"
``quoted string''
$ printf "four\\\\nthree\\\ntwo\\none\n"
four\nthree\ntwo
one
$ echo "var=\`echo \$var\`"
var=`echo $var`
$ echo "var=\$(echo \$var)"
var=$(echo $var)

可變擴充套件:

$ var=variable echo "$var \$var \\$var \\\$var"
variable $var \variable \$var

命令替換:

$ var=variable echo "var=`echo $var`"
var=variable
$ var=variable echo "var=$(echo $var)"
var=variable

刪除換行符:

$ echo "multi\
> -line"
multi-line