linux中shell变量$#,$@,$*,$?,$0,$1,$2的含义解释

 

linux中shell变量$#,$@,$0,$1,$2的含义解释: 

 

 

 

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） 
$- 
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：

1 #!/bin/bash

  2 #

  3 printf "The complete list is %s\n" "$$"

  4 printf "The complete list is %s\n" "$!"

  5 printf "The complete list is %s\n" "$?"

  6 printf "The complete list is %s\n" "$*"

  7 printf "The complete list is %s\n" "$@"

  8 printf "The complete list is %s\n" "$#"

  9 printf "The complete list is %s\n" "$0"

10 printf "The complete list is %s\n" "$1"

11 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

Have a nice day!!!