关于shell编程，为什么程序不能运行希望的效果？

lihui19891118

#!/bin/bash
#hello
echo "welcome to use AUTOUSE"
echo "do you want load usb(y/n)?"
read ANSWER
if  [ $ANSWER="Y" -o $ANSWER="y" ]
   then mount -t vfat /dev/sdb1 /mnt/usb
    echo "do you want copy files to /root/(y/n)?"
   read ANSWER
     while [ $ANSWER="y" -o  $ANSWER="Y" ]
      do      
        ls -a /mnt/usb
        echo "type the filename you want to copy"
        read FILE
       cp "/mnt/usb/$FILE"  /root/
       if [ $? -eq 0 ];then
           echo "copy finished"
       else
         echo "copy erroed"
      fi
     echo "any other files(y/n)?"
     read ANSWER
  done
fi

echo "do you want to copy files to usb(y/n)?"
read ANSWER
while [ $ANSWER="y" -o $ANSWER="Y" ]
do
   -ls a /root
    echo "type the filename you want to copy to usb"
   read FILE
   cp "/root/$FILE" /mnt/usb
   if [ $? -eq 0 ];then
       echo "copy file finished"
       else
      echo "copy file errored"
  fi
  echo "any other files(y/n)?"
  read ANSWER
done

echo "do you want to umount usb(y/n)?"
read ANSWER
if [ $ANSWER="y" -o $ANSWER="Y" ];then
  umount /mnt/usb
else
echo "Haven't umount!"
fi
echo "GoodBye!"
为什么不论输入的是y或者n，它都能执行，并且一直在第一个while语问停留，麻烦各位帮我看下，刚接触shell编程没有多久，谢谢

lihui19891118

怎么没有人回答呢？

MMMIX

回复 1# lihui19891118


    Try this, and compare with yours:

1. 
   
2. 
   
3. #!/bin/bash
   
4. 
   
5. echo "Type Y/N"
   
6. read A
   
7. if [ "$A" = "Y" -o "$A" = "y" ]; then
   
8.         echo "Y"
   
9. else
   
10.         echo "N"
    
11. fi
    

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