What is the command line equivalent of the Nautilus feature called "Safely Remove Drive". Specifically, I am removing a USB flash drive.
udisks command is most likely what you are looking for.
sudo unmount /dev/sdXY will work, udisks can do this without root level (sudo) permissions.
If you have a drive
/dev/sdXY, mounted, where X is a letter representing your usb disk and Y is the partition number (usually 1), you can use the following commands to safely remove the drive:
udisks --unmount /dev/sdXY udisks --detach /dev/sdX
For a practical example, if I have the partition
/dev/sdb1 mounted, I would run this to unmount and detach it:
udisks --unmount /dev/sdb1 udisks --detach /dev/sdb
If your drive is not mounted, or was never mounted, simply use the second command:
udisks --detach /dev/sdb
I originally found this through this question: https://superuser.com/a/430470/176493.
In the newer ubuntu distributions (I'm unsure of when the switch occurred), udisks2 is installed instead of udisks.
Mirroring the commands above, to unmount and detach a disk with udisks2:
udisksctl unmount -b /dev/sdXY udisksctl power-off -b /dev/sdX
Example if my drive is
udisksctl unmount -b /dev/sdb1 udisksctl power-off -b /dev/sdb
Similarly to above, power-off can be used to detach the drive even if there are no partitions mounted, or no partition was ever mounted:
udisksctl power-off -b /dev/sdb
The actual equivalent to Nautilus Mount/Unmount operation is
gvfs-mount -m -d /dev/ice /some/directory and
gvfs-mount -u /some/directory. This uses the same API that Nautilus uses, GIO virtual file system (gvfs), which provides different tools to use several services as mount points, such smb, NFS, FTP, block devices, etc.
To identify which device you need to unmount just use
gvfs-mount -l which should be enough.
This solution has the peculiarity that it doesn't require for elevated permissions, since everything is managed by the umount/gvfsd/polkit services, which further resemblances the similarity with Nautilus behavior.
Once you know the device, possibly using the
df info as in @rcpao answer, the best way to "eject" the disk is, imho, using the same command that the graphical interface is using:
udisksctl unmount --block-device /dev/sdc1
I have a script to do a backup to a disk that I know will mount under
/media/romano/movlin, and after the backup I do:
sync udisksctl unmount -b $(mount | grep movlin | cut -d" " -f1)
mount | grep movlin | cut -d" " -f1 will extract the device that is mounted under the label "movlin", (would be
/dev/sdc1 in that case), and then it unmounts it.
df to find the mount point of your flash drive.
rcpao@bun:~$ df Filesystem 1K-blocks Used Available Use% Mounted on /dev/mapper/ubuntu--vg-root 1916153032 658404668 1160390336 37% / none 4 0 4 0% /sys/fs/cgroup udev 16438692 4 16438688 1% /dev tmpfs 3289976 2156 3287820 1% /run none 5120 0 5120 0% /run/lock none 16449860 18768 16431092 1% /run/shm none 102400 48 102352 1% /run/user /dev/sda1 240972 98990 129541 44% /boot /dev/sdc1 60915712 20992 60894720 1% /media/rcpao/SD024-64GB
Unmount using either /dev/sdc1 or /media/rcpao/SD024-64GB.
rcpao@bun:~$ sudo umount /dev/sdc1 [sudo] password for rcpao: rcpao@bun:~$
rcpao@bun:~$ sudo umount /media/rcpao/SD024-64GB [sudo] password for rcpao: rcpao@bun:~$
You should be able to see the flash drive's eject icon disappear in nautilus as soon as umount finishes.
eject from the eject package:
sudo eject /dev/sdX
umount all partitions, and put the device in a state that you must remove and reattach it to remount.