<div class="content" name="VDS_CREATE_VDISK_PARAMETERS" uuid="e8b4357a-59a1-47cf-9c7b-1a64f6281575"><p>The VDS_CREATE_VDISK_PARAMETERS structure contains the
parameters to be used when a <a href="8eef5d42-22d7-4302-aed9-12face91505a#gt_1fbc35d5-bcf5-4ce7-9449-4197a1671440" data-linktype="relative-path">virtual
disk</a> is created.</p><dl>
<dd>
<div><pre> typedef struct _VDS_CREATE_VDISK_PARAMETERS {
   GUID UniqueId;
   ULONGLONG MaximumSize;
   ULONG BlockSizeInBytes;
   ULONG SectorSizeInBytes;
   [string] LPWSTR pParentPath;
   [string] LPWSTR pSourcePath;
 } VDS_CREATE_VDISK_PARAMETERS,
  *PVDS_CREATE_VDISK_PARAMETERS;
</pre></div>
</dd></dl><p><b>UniqueId:</b>  A unique and non-zero <a href="../ms-dtyp/4926e530-816e-41c2-b251-ec5c7aca018a" data-linktype="relative-path"><span>GUID</span></a> value to be
assigned to the virtual disk.</p><p><b>MaximumSize:</b>  The maximum virtual
size, in bytes, of the virtual disk object.</p><p><b>BlockSizeInBytes:</b>  The internal
block size, in bytes, of the virtual disk object. If the virtual disk object
being created is a <a href="8eef5d42-22d7-4302-aed9-12face91505a#gt_f738286f-68d6-4890-a658-efcf815313ae" data-linktype="relative-path">differencing
disk</a>, this value MUST be 0. If the virtual disk object being created is not
a differencing disk, setting this value to 0 causes the virtual disk object
being created to use the default block size.<a id="Appendix_A_Target_50"></a><a aria-label="Product behavior note 50" href="6b2552ee-ba27-409f-99a8-18841573327a#Appendix_A_50" data-linktype="relative-path">&lt;50&gt;</a></p><p><b>SectorSizeInBytes:</b>  Internal sector
size, in bytes, of the virtual disk object. This value MUST be set to 512
(CREATE_VIRTUAL_DISK_PARAMETERS_DEFAULT_SECTOR_SIZE).</p><p><b>pParentPath:</b>  A null-terminated
wide-character string containing an optional path to a parent virtual disk
object. This member associates the new virtual <a href="8eef5d42-22d7-4302-aed9-12face91505a#gt_511ca852-83e7-4a0c-8081-06e36436876b" data-linktype="relative-path">hard disk</a> with an existing
virtual hard disk. Used when creating a differencing disk. The differencing
disk gets its size from its parent.</p><dl>
<dd>
<p>A differencing disk represents the current state of
the virtual disk as a set of modified blocks in comparison to a parent disk. A
differencing disk is not independent; it depends on the parent disk to be fully
functional. A differencing disk MUST be created using the
CREATE_VIRTUAL_DISK_FLAG_NONE flag. The parent disk can be created using either
the CREATE_VIRTUAL_DISK_FLAG_NONE or
CREATE_VIRTUAL_DISK_FLAG_FULL_PHYSICAL_ALLOCATION flag. The parent disk can be
another differencing disk.</p>
</dd></dl><p><b>pSourcePath:</b>  A null-terminated
wide-character string containing an optional path to a source of data to be
copied to the new virtual hard disk. When <i>pSourcePath</i> is specified, data
from the input <a href="8eef5d42-22d7-4302-aed9-12face91505a#gt_5dcddf1d-f76c-48ea-aef3-208bbc2eea77" data-linktype="relative-path">virtual disk
file</a> is copied block for block from the input virtual disk file to the
created virtual disk file. There is no parent-child relationship established.</p></div>