Linux Shell脚本编程－－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