前言
macOS 使用 diskutil 命令格式化 U 盘，记录一下操作步骤。
环境说明
macOS
% sw_vers
ProductName: macOS
ProductVersion: 12.0.1
BuildVersion: 21A55
diskutil 命令如下
% diskutil
Disk Utility Tool
Utility to manage local disks and volumes
Most commands require an administrator or root user
WARNING: Most destructive operations are not prompted
Usage: diskutil [quiet] <verb> <options>, where <verb> is as follows:
list (List the partitions of a disk)
info[rmation] (Get information on a specific disk or partition)
listFilesystems (List file systems available for formatting)
listClients (List all current disk management clients)
activity (Continuous log of system-wide disk arbitration)
u[n]mount (Unmount a single volume)
unmountDisk (Unmount an entire disk (all volumes))
eject (Eject a disk)
mount (Mount a single volume)
mountDisk (Mount an entire disk (all mountable volumes))
enableJournal (Enable HFS+ journaling on a mounted HFS+ volume)
disableJournal (Disable HFS+ journaling on a mounted HFS+ volume)
moveJournal (Move the HFS+ journal onto another volume)
enableOwnership (Exact on-disk User/Group IDs on a mounted volume)
disableOwnership (Ignore on-disk User/Group IDs on a mounted volume)
rename[Volume] (Rename a volume)
verifyVolume (Verify the file system data structures of a volume)
repairVolume (Repair the file system data structures of a volume)
verifyDisk (Verify the components of a partition map of a disk)
repairDisk (Repair the components of a partition map of a disk)
resetFusion (Reset the components of a machine's Fusion Drive)
eraseDisk (Erase an existing disk, removing all volumes)
eraseVolume (Erase an existing volume)
reformat (Erase an existing volume with same name and type)
eraseOptical (Erase optical media (CD/RW, DVD/RW, etc.))
zeroDisk (Erase a disk, writing zeros to the media)
randomDisk (Erase a disk, writing random data to the media)
secureErase (Securely erase a disk or freespace on a volume)
partitionDisk ((re)Partition a disk, removing all volumes)
addPartition (Create a new partition to occupy free space)
splitPartition (Split an existing partition into two or more)
mergePartitions (Combine two or more existing partitions into one)
resizeVolume (Resize a volume, increasing or decreasing its size)
appleRAID <verb> (Perform additional verbs related to AppleRAID)
coreStorage <verb> (Perform additional verbs related to CoreStorage)
apfs <verb> (Perform additional verbs related to APFS)
diskutil <verb> with no options will provide help on that verb
diskutil 命令可以进行很多磁盘操作，本例只为格式化 U 盘。
步骤
查看
先插入 U 盘，使用 list 子命令查看一下是 disk 号
% diskutil list
/dev/disk0 (internal, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *1.0 TB disk0
1: EFI EFI 314.6 MB disk0s1
2: Apple_APFS Container disk1 1.0 TB disk0s2
/dev/disk1 (synthesized):
#: TYPE NAME SIZE IDENTIFIER
0: APFS Container Scheme - +1.0 TB disk1
Physical Store disk0s2
1: APFS Volume Macintosh HD - Data 617.4 GB disk1s1
2: APFS Volume Preboot 534.6 MB disk1s2
3: APFS Volume Recovery 1.1 GB disk1s3
4: APFS Volume VM 20.5 KB disk1s4
5: APFS Volume Macintosh HD 15.7 GB disk1s5
6: APFS Snapshot com.apple.os.update-... 15.7 GB disk1s5s1
/dev/disk2 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *16.0 GB disk2
1: Microsoft Basic Data 217.1 KB disk2s1
2: EFI NO NAME 2.9 MB disk2s2
3: Apple_HFS PVE 1.0 GB disk2s3
4: Microsoft Basic Data 307.2 KB disk2s4
可以看到， /dev/disk2 这个 U 盘的大小为 16 GiB，本例就已格式化 /dev/disk2 为例。
取消 U 盘挂载
使用 umountDisk 子命令
% sudo diskutil umountDisk /dev/disk2
Unmount of all volumes on disk2 was successful
覆盖所有扇区
使用 zeroDisk 子命令
% sudo diskutil zeroDisk /dev/disk2
Started erase on disk2
#此处会有进度条
Finished erase on disk2
格式化 U 盘
使用 eraseDisk 子命令，注意，本例将 U 盘格式化为 ExFAT 格式，并且将名字设置为 Extreme
% sudo diskutil eraseDisk ExFAT Extreme /dev/disk2
Password:
Started erase on disk2
Unmounting disk
Creating the partition map
Waiting for partitions to activate
Formatting disk2s2 as ExFAT with name Extreme
Volume name : Extreme
Partition offset : 411648 sectors (210763776 bytes)
Volume size : 30865408 sectors (15803088896 bytes)
Bytes per sector : 512
Bytes per cluster: 32768
FAT offset : 2048 sectors (1048576 bytes)
# FAT sectors : 4096
Number of FATs : 1
Cluster offset : 6144 sectors (3145728 bytes)
# Clusters : 482176
Volume Serial # : 61b6d68b
Bitmap start : 2
Bitmap file size : 60272
Upcase start : 4
Upcase file size : 5836
Root start : 5
Mounting disk
Finished erase on disk2
这样完成格式化 U 盘了。