linux中shell变量$#,$@,$0,$1,$2的含义解释
Posted
tags:
篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了linux中shell变量$#,$@,$0,$1,$2的含义解释相关的知识,希望对你有一定的参考价值。
linux中shell变量$#,[email protected],$0,$1,$2的含义解释: 变量说明: $$ Shell本身的PID(ProcessID) $! Shell最后运行的后台Process的PID $? 最后运行的命令的结束代码(返回值) $- 使用Set命令设定的Flag一览 $* 所有参数列表。如"$*"用「"」括起来的情况、以"$1 $2 … $n"的形式输出所有参数。 [email protected] 所有参数列表。如"[email protected]"用「"」括起来的情况、以"$1" "$2" … "$n" 的形式输出所有参数。 $# 添加到Shell的参数个数 $0 Shell本身的文件名 $1~$n 添加到Shell的各参数值。$1是第1参数、$2是第2参数…。
示例: 1 #!/bin/bash 2 # 3 printf "The complete list is %s\n" "$$" 4 printf "The complete list is %s\n" "$!" 5 printf "The complete list is %s\n" "$?" 6 printf "The complete list is %s\n" "$*" 7 printf "The complete list is %s\n" "[email protected]" 8 printf "The complete list is %s\n" "$#" 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" "$2
结果: [[email protected] ~]$ 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