How to make a partition on a RAW USB flash disk by programming?

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Briefly, here are the steps:
1. Use CreateFile to open PhysicalDriveX, that is the USB Flash disk
2. IOCTL_DISK_GET_DRIVE_GEOMETRY_EX to get the physical disk's geometry ( we need some information in it to fill partition data)
3. IOCTL_DISK_CREATE_DISK to creates an empty partition.
4. IOCTL_DISK_SET_DRIVE_LAYOUT_EX to repartition a disk as specified.
Note: use IOCTL_DISK_UPDATE_PROPERTIES to synchronize system view after IOCTL_DISK_CREATE_DISK and IOCTL_DISK_SET_DRIVE_LAYOUT_EX.
e.g. a 1GB size flash disk,
pBuf->PartitionEntry[0].PartitionStyle = PARTITION_STYLE_MBR;
pBuf->PartitionEntry[0].StartingOffset.QuadPart = 0x10000;//64KB
pBuf->PartitionEntry[0].PartitionLength.QuadPart = 0x1e200000; //Donot exceed DiskGeo.DiskSize
pBuf->PartitionEntry[0].PartitionNumber = 1;
pBuf->PartitionEntry[0].RewritePartition = TRUE;
pBuf->PartitionEntry[0].Mbr.PartitionType = PARTITION_FAT32;
pBuf->PartitionEntry[0].Mbr.BootIndicator = TRUE;
pBuf->PartitionEntry[0].Mbr.RecognizedPartition = TRUE;
pBuf->PartitionEntry[0].Mbr.HiddenSectors = 0x80; //StartingOffset/(DiskGeo.BytesPerSector) = 0x10000/0x200