$0 $1

linux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）
$*
所有参数列表。如"$*"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…。

eric@eric-virtual-machine:~$ cat ethdev1/variable.sh 
printf "The complete list \$$ is %s\n" "$$"
printf "**********\n"
printf "The complete list \$! is %s\n" "$!"
printf "**********\n"
printf "The complete list \$? is %s\n" "$?"
printf "**********\n"
printf "The complete list \$* is %s\n" "$*"
printf "**********\n"
printf "The complete list \$@ is %s\n" "$@"
printf "**********\n"
printf "The complete list \$# is %s\n" "$#"
printf "**********\n"
printf "The complete list \$0 is %s\n" "$0"
printf "**********\n"
printf "The complete list \$1 is %s\n" "$1"
printf "**********\n"
printf "The complete list \$2 is %s\n" "$2"
printf "**********\n"
eric@eric-virtual-machine:~$ ethdev1/variable.sh QQ 809512722
The complete list $$ is 7674
**********
The complete list $! is 
**********
The complete list $? is 0
**********
The complete list $* is QQ 809512722
**********
The complete list $@ is QQ
The complete list $@ is 809512722
**********
The complete list $# is 2
**********
The complete list $0 is ethdev1/variable.sh
**********
The complete list $1 is QQ
**********
The complete list $2 is 809512722
**********