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  • 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
    " "$$"
      4 printf "The complete list is %s
    " "$!"
      5 printf "The complete list is %s
    " "$?"
      6 printf "The complete list is %s
    " "$*"
      7 printf "The complete list is %s
    " "$@"
      8 printf "The complete list is %s
    " "$#"
      9 printf "The complete list is %s
    " "$0"
     10 printf "The complete list is %s
    " "$1"
     11 printf "The complete list is %s
    " "$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!!!
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  • 原文地址:https://www.cnblogs.com/kakaisgood/p/8335716.html
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