逃离

\ escapes 保留以下字符值，除非后面的字符是换行符，在这种情况下删除了\和换行符。

转义特殊字符：

$ echo \"quoted text\"
"quoted text"
$ echo \`\`quoted text\'\'
``quoted text''
$ echo 'single-quotes inside of a '\''single-quoted'\'' string'
single-quotes inside of a 'single-quoted' string
$ printf format\ with\ %s spaces
format with spaces
$ printf %s\\n \$var
$var

删除换行符：

$ echo multi\
> -line
multi-line