ogra@pi3:~$ sudo sgdisk -p /dev/mmcblk0

***************************************************************
Found invalid GPT and valid MBR; converting MBR to GPT format
in memory. 
***************************************************************

Disk /dev/mmcblk0: 7843840 sectors, 3.7 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): 01426CDA-8E25-4E81-9EAB-04EB9750FFB3
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 7843806
Partitions will be aligned on 2048-sector boundaries
Total free space is 2070 sectors (1.0 MiB)

Number  Start (sector)    End (sector)  Size       Code  Name
   1            2048          264191   128.0 MiB   0700  Microsoft basic data
   2          264192         7843750   3.6 GiB     8300  Linux filesystem
ogra@pi3:~$