• 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

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  • 原文地址:https://www.cnblogs.com/jimeper/p/4335698.html
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