Custom functions in the shell

Customizing a function for printing function parameters

[[email protected] shell]# vim fun1.sh#!/bin/bashpri(){        echo "第一个参数为 $1"        echo "第二个参数为 $2"        echo "文件名为 $0"        echo "总共有$#个参数"       }pri a b       #调用函数

Execution results

[[email protected] shell]# sh fun1.sh第一个参数为 a第二个参数为 b文件名为 fun1.sh总共有2个参数

Customize a function that will add calculations

[[email protected] shell]# vim fun2.sh#!/bin/bashsum (){      s=$[$1+$2]      echo $s      }sum 6 9

Execution results

[[email protected] shell]# sh -x fun2.sh+ sum 6 9+ s=15+ echo 1515

Customize an input network card name to display IP functions

[[email protected] shell]# vim fun3.sh#!/bin/baship (){      a=`ifconfig |grep -A1 "$1: "`      b=`ifconfig |grep -A1 "$1: "|awk ‘/inet/ {print $2}‘`      if [ -z "$a" ]      then          echo "网卡不存在"          exit      elif [ -z "$b" ]      then          echo "网卡没有定义ip"          exit      else          echo "$b"      fi}read -p "请输入网卡名：" ethip $eth

Execution results

[[email protected] shell]# sh fun3.sh请输入网卡名：ens33192.168.130.116[[email protected] shell]# sh fun3.sh请输入网卡名：ens37网卡没有定义ip[[email protected] shell]# sh fun3.sh请输入网卡名：ens38网卡不存在

Custom functions in the shell