sergio-j-cazzolato@localhost:~$ df -h
Filesystem      Size  Used Avail Use% Mounted on
udev            455M     0  455M   0% /dev
tmpfs            93M  6.8M   86M   8% /run
/dev/mmcblk0p2  450M  382M   35M  92% /writable
/dev/loop0       67M   67M     0 100% /
/dev/loop1       86M   86M     0 100% /lib/modules
tmpfs           461M  4.0K  461M   1% /etc/fstab
tmpfs           461M     0  461M   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           461M     0  461M   0% /sys/fs/cgroup
tmpfs           461M     0  461M   0% /tmp
tmpfs           461M     0  461M   0% /mnt
tmpfs           461M     0  461M   0% /var/lib/sudo
tmpfs           461M     0  461M   0% /media
/dev/mmcblk0p1  127M   22M  105M  18% /boot/uboot
cgmfs           100K     0  100K   0% /run/cgmanager/fs
/dev/loop2       67M   67M     0 100% /snap/core/1443
/dev/loop3       86M   86M     0 100% /snap/pi2-kernel/22
/dev/loop4      5.9M  5.9M     0 100% /snap/pi3/6
tmpfs            93M     0   93M   0% /run/user/1000
/dev/loop5       69M   69M     0 100% /snap/core/2466
sergio-j-cazzolato@localhost:~$ sudo sgdisk -p /dev/mmcblk0
Caution: invalid main GPT header, but valid backup; regenerating main header
from backup!

Caution! After loading partitions, the CRC doesn't check out!
Warning! Main partition table CRC mismatch! Loaded backup partition table
instead of main partition table!

Warning! One or more CRCs don't match. You should repair the disk!

Invalid partition data!