inux中shell变量$#,$@,$0,$1,$2的含义解释

inux中shell变量$#,$@,$0,$1,$2的含义解释: 
变量说明: 
$$  ：  Shell本身的PID（ProcessID） 
$!   ：  Shell最后运行的后台Process的PID 
$?  ：  最后运行的命令的结束代码（返回值） 
$-   ：  使用Set命令设定的Flag一览 
$*   ：  所有参数列表。如"$*"用「"」括起来的情况、以"$1 $2 … $n"的形式输出所有参数。 
$@ ： 所有参数列表。如"$@"用「"」括起来的情况、以"$1" "$2" … "$n" 的形式输出所有参数。 
$#   ： 添加到Shell的参数个数 
$0   ： Shell本身的文件名 
$1～$n  ： 添加到Shell的各参数值。$1是第1参数、$2是第2参数…。 

示例：

#!/bin/bash printf "The complete list is %s\n" "$$" printf "The complete list is %s\n" "$!" printf "The complete list is %s\n" "$?" printf "The complete list is %s\n" "$*" printf "The complete list is %s\n" "$@" printf "The complete list is %s\n" "$#" printf "The complete list is %s\n" "$0" printf "The complete list is %s\n" "$1" printf "The complete list is %s\n" "$2

结果：

[Aric@localhost ~]$ bash params .sh 123456 QQ

The complete list is 24249

The complete list is

The complete list is 0

The complete list is 123456 QQ

The complete list is 123456

The complete list is QQ

The complete list is 2

The complete list is params .sh

The complete list is 123456

The complete list is QQ