DD脚本和操作数预期err r

Question

我正在尝试实现一行代码，以防止用户擦除主机闪存盘(任何低于110 GB的内容)。

#!/bin/bash
RED='\033[0;31m'
NC='\033[0m'
END='\033[0m'
FLASH='\e[5m'
dt=`date '+%m/%d/%Y_%H:%M:%S'`
echo -e "STILL BE CAREFUL!! SIZE CHECK IS STILL NON-FUNCTIONAL"
echo "Inspect the drive for multiple boot/storage/recovery partitions. Check out the README.odt for reference photos."
sudo gnome-disks
echo "Showing list of drives: "
sudo fdisk -l | grep -i "Disk /"
echo "What drive are you attempting to wipe? Do not include /dev/"
read drive
size= sudo fdisk -l | grep -i "Disk /dev/$drive" | awk -F" " {'print $3'}
printf %.0f $size
if (( $size <= 110 ))
then
        echo -e "$size"
        echo -e "${RED}${FLASH}Error: You are trying to wipe a disk that is less than 110 GB. There's a high chance this is the host flashdrive. If you are sure this is the correct drive use\n ${END}${RED}sudo dd if=/dev/urandom of=/dev/<drive here> bs=1M status=progress${NC}"
else
        echo -e "${RED}Now wiping drive /dev/$drive!${END}"
        sudo dd if=/dev/urandom of=/dev/$drive bs=1M status=progress
        echo -e "${RED}${FLASH}Wiping has completed at $dt !!!${END}"
echo "Drive in question should only have one main partition. See README.odt for reference."
sudo gnome-disks

fi
echo "Please enter Ctrl + C to exit!"
sleep 10000

如果我尝试擦除sda，即8.7GB，我希望它会抛出我创建的错误。相反，它说，预期操作数错误，然后继续擦除测试闪存盘无论如何。

Answer 1

变量size总是等于零(实际上对几乎整个脚本都没有设置)。我想你的意思是在分配中的等号后立即加一个反号，在行尾再加上一个。但绝对不要用后排。这就是其中的一个例子。它们很容易被忽略或误读为单引号，而且它们很难嵌套，等等。

该行表示“将size的值设置为null，并只将其传递到sudo环境中”。

由于size未设置，您将得到if语句的“操作数预期”错误，printf也输出"0“。

将这一行改为：

size=$(sudo fdisk -l | awk -F " " -v drive=$drive 'BEGIN {IGNORECASE = 1} $0 ~ "/Disk /dev/" drive {print $3}')

注意，我还将单引号移到它们在AWK命令中的正确位置，并将grep函数移动到AWK命令中。

以下是其他几行更正后的行：

dt=$(date '+%m/%d/%Y_%H:%M:%S')
printf '%.0f\n' "$size"

您可以省略双括号内的美元符号：

if (( size <= 110 ))