Linux shell中的函数定义、传参和调用

Linux shell中的函数定义、传参和调用：

函数定义语法：

[ function ] functionName [()] {

}

示例：

#!/bin/bash

# get limit
if [ $# -eq 1 ] && [ $1 -gt 0 ]; then
  limit=$1
  echo -e "\nINFO: input limit is $limit"
else
  limit=-1
  echo -e "\nWARN: input limit for initDynamic is null!"
fi


host_arr=()

init(){
  host_arr[${#host_arr[@]}]=192.168.1.120
  host_arr[${#host_arr[@]}]=192.168.1.121
  host_arr[${#host_arr[@]}]=192.168.1.122
}

reset(){
  host_arr=()
}

showResult(){
  echo -e "------ show mode 1 -----"
  echo "${host_arr[@]}"
  
  echo -e "\n------ show mode 2 -----"
  for i in ${host_arr[@]}; do
    echo $i
  done

  echo -e "\n------ show mode 3 -----"
  max=${#host_arr[@]}
  for ((i=0;i<$max;i++)); do
    echo ${host_arr[$i]};
  done
}

function initDynamic () {
  for ((i=0,j=0;i<$1;i++)); do
    j=$(expr 120 + $i)
    host_arr[${#host_arr[@]}]=192.168.1.$j
  done
}


echo -e "\ninit result: "
reset
init
showResult

echo -e "\ninitDynamic $limit result: "
reset
initDynamic $limit
showResult

echo ""

执行结果如下：