Uly.me

cloud engineer

format

Bash Reformat Numbers

How to reformat numbers in Bash.

$ n=1023555
$ m=$(numfmt --to=si n)
$ echo $m
1.1M

Other options

--to=none     # no scaling. Output: 1023555
--to=si       # International System of Units (SI) standard. Output 1.1M
--to=iec      # International Electrotechnical Commission (IEC) standard. Output: 1.1Mi 
--to=iec-i    # International Electrotechnical Commission (IEC) standard. Output: 1.1M
--to=auto     # ‘auto’ can only be used with --from.

fmtnum

Linux Format USB Drive

Here’s how to format a USB drive on Linux.

Plug in the USB drive to see mount point.

# scan for all drives
df -Th
Filesystem     Type     Size  Used Avail Use% Mounted on
/dev/sdc1      fuseblk   30G   66M   30G   1% /media/ulysses/451B99AF225B48EC

Unmount USB drive.

umount /dev/sdc1

Choose a file system type and run the appropriate format command.

# nfts format
mkfs.ntfs /dev/sdc1
# vfat format
mkfs.vfat /dev/sdc1
# ext4 format
mkfs.ext4 /dev/sdc1

Determine USB Format Type

Here’s how to determine what type of USB format a thumb drive is in Linux.

  • df -Th (shows the file system type)
  • lsblk (shows the block devices)
  • lsusb (show usb ports and devices)
  • fdisk -l (displays the USB format type)

To display, use “fdisk -l” to display either NTFS, FAT32 or exFAT32.