Section 64.1: 简单示例

解码 URL

http%3A%2F%2Fwww.foo.com%2Findex.php%3Fid%3Dqwerty

使用此命令解码 URL

echo "http%3A%2F%2Fwww.foo.com%2Findex.php%3Fid%3Dqwerty" | sed -e "s/%\([0-9A-F][0-9AF]\)/\\\\\x\1/g" | xargs -0 echo -e

解码后的 URL（命令结果）

http://www.foo.com/index.php?id=qwerty

Section 64.2: 使用 printf 解码字符串

#!bin/bash

$ string='Question%20-%20%22how%20do%20I%20decode%20a%20percent%20encoded%20string%3F%22%0AAnswer%20%20%20-%20Use%20printf%20%3A)'
$ printf '%b\n' "${string//%/\\x}"

# the result
Question - "how do I decode a percent encoded string?"
Answer - Use printf :)