my shell script

1.Shell中控制流结构

#case 语句 

case $var in
    val1)
        body1
        ;;

    val2|val3)
        body2&3
        ;;
esac

tab同if。可以都省

 

      1 #!/bin/sh
      2
      3 m=Oct
      4
      5 case $m in
      6     Jan)
      7         mm=01
      8         ;;
      9     Oct)
     10         mm=10
     11         ;;
     12 esac
     13
     14 echo $mm

 

#sh ...sh

#10

 

2.文件存在

      4 if [ ! -e vb ];then
      5 touch vb
      6 fi

 

3.

     64     while true;do
     65         echo  "Make sure USB Mass Storage is inserted."
     66         echo  "----------------------------------------------------------------"
     67         echo  "Press enter to continue..."
     68         echo  "----------------------------------------------------------------"
     69     read Arg
     70     case $Arg in
     71         Y|y|YES|yes)
     72             break
     73             ;;
     74         N|n|NO|no)
     75             exit
     76             ;;
     77         "")
     78             break
     79             ;;
     80     esac
     81     done

 

4.

     23 while true;do
     24   echo "please input DHCP server IP address:"
     25         read DHCP_SERVER
     26         echo ${DHCP_SERVER}|grep "^[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9
        ]\{1,3\}$" > /dev/null
     27         num=$?
     28         if [ $num = 1 ]
     29         then
     30                 echo error ip,please enter correct
     31         else
     32                 export DHCPSERVER=${DHCP_SERVER}
     33                 break
     34         fi
     35 done

 

5.

 

 

6.

 

 

 

 

7.