shell基本语法

多命令执行逻辑

https://blog.csdn.net/u011630575/article/details/97613695

同时执行多条语句
command1 || {
statement1
statement2
statement3
}

if

if如果有else分支，则if分支里必须要执行命令，否则报错。

for

https://blog.csdn.net/weixin_44175418/article/details/124444938

• 文件遍历：

  for file in $(ls /opt/control-server/*console.log)
  do 
  fileDate=${file##*/}
  fileDate=${fileDate%console*}
  fileDateSeconds=$(date -d "${fileDate}" +%s)
  echo "file:${file},fileDateSeconds:${fileDateSeconds}"
  # 10天之前的日志删除
  if [ ${fileDateSeconds} -le $((${curDateSeconds} - 10*24*60*60)) ];then
      echo "发现过期(超过10天)日志文件${file}，删除"  
      sudo rm -f ${file}
  fi
  done

• 连续整数遍历
  下面是批量开启防火墙端口的代码

  for port in {9901..9909}
  do
  result=$(firewall-cmd --query-port=$port/tcp --zone=public)
  if [[ "no" =  $result ]];then
    firewall-cmd --permanent --add-port=$port/tcp
  fi
  
  result=$(firewall-cmd --query-port=$port/udp --zone=public)
  if [[ "no" =  $result ]];then
    firewall-cmd --permanent --add-port=$port/udp
  fi
  done

• 双重循环
  https://zhuanlan.zhihu.com/p/511987104

包含子shell文件

http://static.kancloud.cn/dlover/linuxbashshell/2009401
. ./t1.fish #将t1.fish引入

eval命令

https://blog.51cto.com/u_10706198/1788573