BusyBox v1.10.2 (Debian 3:1.10.2.legal-1osso30+0m5) built-in shell (ash)
Enter 'help' for a list of built-in commands.

~ $ sudo gainroot
Root shell enabled


BusyBox v1.10.2 (Debian 3:1.10.2.legal-1osso30+0m5) built-in shell (ash)
Enter 'help' for a list of built-in commands.

/home/user #
/home/user # echo "unit: sectors
> > > /dev/mmcblk0p1 : start= 64, size= 44400640, Id=c
> > > /dev/mmcblk0p2 : start= 44433472, size= 16744448, Id=83> > > /dev/mmcblk0p3 : start= 61177920, size= 1572864, Id=82
> > > /dev/mmcblk0p4 : start= 0, size= 0, Id= 0" > table
/home/user #
/home/user # sfdisk --no-reread /dev/mmcblk0 < table

Disk /dev/mmcblk0: 982528 cylinders, 4 heads, 16 sectors/track
Old situation:
Units = cylinders of 32768 bytes, blocks of 1024 bytes, counting from 0

Device Boot Start End #cyls #blocks Id System
/dev/mmcblk0p1 1 693760 693760 22200320 c W95 FAT32 (LBA)
/dev/mmcblk0p2 693761 955904 262144 8388608 83 Linux
/dev/mmcblk0p3 955905 980480 24576 786432 82 Linux swap / Solaris
/dev/mmcblk0p4 0 - 0 0 0 Empty
New situation:
Units = sectors of 512 bytes, counting from 0

Device Boot Start End #sectors Id System
/dev/mmcblk0p1 64 44400703 44400640 c W95 FAT32 (LBA)
/dev/mmcblk0p2 44433472 61177919 16744448 83 Linux
/dev/mmcblk0p3 61177920 62750783 1572864 82 Linux swap / Solaris
/dev/mmcblk0p4 0 - 0 0 Empty
Warning: no primary partition is marked bootable (active)
This does not matter for LILO, but the DOS MBR will not boot this disk.
Successfully wrote the new partition table

Re-reading the partition table ...
BLKRRPART: Device or resource busy
The command to re-read the partition table failed
Reboot your system now, before using mkfs

If you created or changed a DOS partition, /dev/foo7, say, then use dd(1)
to zero the first 512 bytes: dd if=/dev/zero of=/dev/foo7 bs=512 count=1
(See fdisk(8).)
/home/user #
/home/user #
/home/user #

sudo gainroot
mkfs.ext3 -L optfs -cc /dev/mmcblk0p2