diskutil from terminal

If you simply type diskutil in Terminal, it will show you this:

Disk Utility Tool

Utility to manage local disks and volumes

Most options require root access to the device

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)

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 (Treat as exact User/Group IDs for a mounted volume)

disableOwnership (Ignore on-disk User/Group IDs for 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)

verifyPermissions (Verify the permissions of a Mac OS X volume)

repairPermissions (Repair the permissions of a Mac OS X volume)

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)

resizeVolume (Resize a volume, increasing or decreasing its size)

splitPartition (Split an existing partition into two or more)

mergePartitions (Combine two or more existing partitions into one)

appleRAID <verb> (Perform additional verbs related to AppleRAID)

coreStorage <verb> (Perform additional verbs related to CoreStorage)

diskutil <verb> with no options will provide help on that verb

For a full manual, in Terminal, type:

man diskutil

Press Q at any time to exit the manual.

Type the word “diskutil” in the Terminal. Instead of pressing return, either control-click or right-button click on the word and choose Open man Page from the contextual menu. Now, if you do not want to use the graphical Disk Utility, you will have a standalone manual page displayed that will assist you in using diskutil from the Terminal.

If you want to customize the visual appearance of your displayed man page, you can select Terminal preferences and find the profile named Man Page.

open -a "Disk Utility"

Use this command if it is your startup disk...

diskutil verify /

Press return.