ShouldBlockRevert function (vsbackup.h)

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Checks the registry for writers that should block revert operations on the specified volume.

Note  This function is only available on Windows Server operating systems.

 

Syntax

HRESULT ShouldBlockRevert(
  [in]  LPCWSTR wszVolumeName,
  [out] bool    *pbBlock
);

Parameters

[in] wszVolumeName

The name of the volume. This name 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)

[out] pbBlock

A pointer to a variable that receives true if the volume contains components from any writers that are listed in the registry as writers that should block revert operations, or false otherwise.

Return value

This function can return one of these values.

Value Meaning
S_OK
 The function succeeded.
E_ACCESSDENIED
 The caller 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_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.

Remarks

The list of writers that should block revert operations is stored in the registry under the following key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\VSS\Settings\WritersBlockingRevert

Requirements

Requirement Value
Minimum supported client None supported
Minimum supported server Windows Server 2008, Windows Server 2003 with SP1 [desktop apps only]
Target Platform Windows
Header vsbackup.h (include VsBackup.h, Vss.h, VsWriter.h)
Library VssApi.lib
DLL VssApi.dll