IVssDifferentialSoftwareSnapshotMgmt2::ChangeDiffAreaMaximumSizeEx method (vsmgmt.h)

Article
10/13/2021

Updates the shadow copy storage area maximum size for a certain volume. This may not have an immediate effect. If the bVolatile parameter is FALSE, the change continues even if the computer is rebooted.

Syntax

HRESULT ChangeDiffAreaMaximumSizeEx(
  [in] VSS_PWSZ pwszVolumeName,
  [in] VSS_PWSZ pwszDiffAreaVolumeName,
  [in] LONGLONG llMaximumDiffSpace,
  [in] BOOL     bVolatile
);

Parameters

[in] pwszVolumeName

The name of the volume that is the source of shadow copies. This volume is associated with a shadow copy storage area on the pwszDiffAreaVolumeName volume.

The name of the volume must be in one of the following formats and must include a trailing backslash (\):

The path of a mounted folder, for example, Y:\MountX\
A drive letter, for example, D:\
A volume GUID path of the form \\?\Volume{GUID}\ (where GUID identifies the volume)

[in] pwszDiffAreaVolumeName

The name of the volume that contains the shadow copy storage area that is associated with the pwszVolumeName volume.

The name of the volume must be in one of the following formats and must include a trailing backslash (\):

The path of a mounted folder
A drive letter with, for example, D:\
A volume GUID path of the form \\?\Volume{GUID}\ (where GUID identifies the volume)

[in] llMaximumDiffSpace

Specifies the maximum size, in bytes, for the shadow copy storage area to use for the volume. If this value is zero, the shadow copy storage area will be deleted. If this value is –1, the maximum size is unlimited.

[in] bVolatile

TRUE to indicate that the effect of calling the ChangeDiffAreaMaximumSizeEx method should not continue if the computer is rebooted; otherwise, FALSE.

The default value is FALSE.

If the llMaximumDiffSpace parameter is zero, the bVolatile parameter must be FALSE.

Return value

This method can return one of these values.

Value	Meaning
S_OK	The shadow copy storage area maximum size was successfully changed.
E_ACCESSDENIED	The caller does not have sufficient backup privileges or is not an administrator.
E_INVALIDARG	One of the parameter values is not valid.
E_OUTOFMEMORY	The caller is out of memory or other system resources.
VSS_E_INSUFFICIENT_STORAGE	The pwszDiffAreaVolumeName volume does not have sufficient free space.
VSS_E_OBJECT_NOT_FOUND	The association between the pwszVolumeName and pwszDiffAreaVolumeName volumes was not found.
VSS_E_PROVIDER_VETO	An expected provider error has occurred. The error code is logged in the event log. For more information, see Event and Error Handling Under VSS.
VSS_E_UNEXPECTED	Unexpected error. The error code is logged in the error log file. For more information, see Event and Error Handling Under VSS. Windows Server 2008, Windows Vista, Windows Server 2003 and Windows XP: This value is not supported until Windows Server 2008 R2 and Windows 7. E_UNEXPECTED is used instead.
VSS_E_VOLUME_IN_USE	A shadow copy is currently using the shadow copy storage area.

Remarks

The ChangeDiffAreaMaximumSizeEx method is identical to the IVssDifferentialSoftwareSnapshotMgmt::ChangeDiffAreaMaximumSize method except for the bVolatile parameter.

Calling the ChangeDiffAreaMaximumSizeEx method with the bVolatile parameter set to FALSE is the same as calling the ChangeDiffAreaMaximumSize method.

ChangeDiffAreaMaximumSizeEx makes the shadow copy storage area explicit, which means that it is not deleted automatically when all shadow copies are deleted.

If the shadow copy storage area does not exist, this method creates it.

Windows Server 2008, Windows Vista and Windows Server 2003: If the shadow copy storage area does not exist, this method does not create it.

To create a shadow copy storage area, use the IVssDifferentialSoftwareSnapshotMgmt::AddDiffArea method.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps only]
Minimum supported server	Windows Server 2008 [desktop apps only]
Target Platform	Windows
Header	vsmgmt.h