Yrurtj

I would like to know if it is possible to get the following information:

Is this UUID (of a block device) mounted or not? (without knowing the mount point)

In spite, I have played along with this half a day, I can't figure it out.

I have at least created some working code below which un-mounts and powers off both of the USB hard drives.

The current version of my code looks like this:

dismount_and_poweroff_external_drives()

{

    name_external_drive_500gb_ntfs='500GB NTFS USB 2.0 HDD'

    name_external_drive_2_0tb_ext4='2.0TB Ext4 USB 3.0 HDD'

    uuid_external_drive_500gb_ntfs='xxxxxxxxxxxxxxxx' # censored

    uuid_external_drive_2_0tb_ext4='xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx' # censored

    path_external_drive_500gb_ntfs="/dev/disk/by-uuid/${uuid_external_drive_500gb_ntfs}"

    path_external_drive_2_0tb_ext4="/dev/disk/by-uuid/${uuid_external_drive_2_0tb_ext4}"



    tput bold; tput setaf 3; printf '%b' "\n${name_external_drive_500gb_ntfs} un-mount\n"; tput sgr0

    # info test ‘-b FILE’: True if FILE exists and is a block special device.

    if [ ! -b "${path_external_drive_500gb_ntfs}" ]

    then

        tput bold; tput setaf 4; printf '%b' "The device is not plugged in or powered on.\n"; tput sgr0

    else

        if umount "${path_external_drive_500gb_ntfs}"

        then

            tput bold; tput setaf 2; printf '%b' "Un-mounting OK.\n"; tput sgr0



            if udisksctl power-off --block-device "${path_external_drive_500gb_ntfs}"

            then

                tput bold; tput setaf 2; printf '%b' "Powering-off OK.\n"; tput sgr0

            else

                tput bold; tput setaf 2; printf '%b' "Powering-off Failed.\n"; tput sgr0

            fi



        else

            tput bold; tput setaf 1; printf '%b' "Un-mounting Failed.\n"; tput sgr0

        fi

    fi



    printf 'n'



    tput bold; tput setaf 3; printf '%b' "\n${name_external_drive_2_0tb_ext4} un-mount\n"; tput sgr0

    # info test ‘-b FILE’: True if FILE exists and is a block special device.

    if [ ! -b "${path_external_drive_2_0tb_ext4}" ]

    then

        tput bold; tput setaf 4; printf '%b' "The device is not plugged in or powered on.\n"; tput sgr0

    else

        if umount "${path_external_drive_2_0tb_ext4}"

        then

            tput bold; tput setaf 2; printf '%b' "Un-mounting OK.\n"; tput sgr0



            if udisksctl power-off --block-device "${path_external_drive_2_0tb_ext4}"

            then

                tput bold; tput setaf 2; printf '%b' "Powering-off OK.\n"; tput sgr0

            else

                tput bold; tput setaf 2; printf '%b' "Powering-off Failed.\n"; tput sgr0

            fi



        else

            tput bold; tput setaf 1; printf '%b' "Un-mounting Failed.\n"; tput sgr0

        fi

    fi



    printf 'n'

}