IVssCreateWriterMetadata::AddComponentDependency method (vswriter.h)
The AddComponentDependency method allows a writer to indicate that a component it manages has an explicit writer-component dependency; that is, another component in another writer must be backed up and restored with it.
Syntax
HRESULT AddComponentDependency(
[in] LPCWSTR wszForLogicalPath,
[in] LPCWSTR wszForComponentName,
[in] VSS_ID onWriterId,
[in] LPCWSTR wszOnLogicalPath,
[in] LPCWSTR wszOnComponentName
);
Parameters
[in] wszForLogicalPath
A null-terminated wide character string containing the logical path of the component (managed by the current writer) that requires a dependency.
[in] wszForComponentName
A null-terminated wide character string containing the component (managed by the current writer) that requires a dependency.
[in] onWriterId
The class ID or VSS_ID (GUID) of the writer managing the component on which the current component depends.
[in] wszOnLogicalPath
The logical path of the component (managed by the writer identified by onWriterId) on which the current component depends.
[in] wszOnComponentName
The name of the component (managed by the writer identified by onWriterId) on which the current component depends.
Return value
The following are the valid return codes for this method.
Value | Meaning |
---|---|
|
The operation was successful. |
|
One of the parameter values is not valid. |
|
The caller is out of memory or other system resources. |
|
The XML document is not valid. Check the event log for details. For more information, see Event and Error Handling Under VSS. |
|
The component specified by wszForLogicalPath and wszForComponentName does not exist. |
|
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
Dependencies upon components managed by the current writer are not permitted.
A dependency requires that both the target of the dependency and the component that depends on the target be restored and backed up together. It does not indicate a priority between the components, although a requester may choose to implement that.
Because the combination of logical name and component name must be unique across all instances of a writer class, the fact that several writers may have the same class ID is not a problem.
This method can be used to declare remote dependencies. A writer can declare a remote dependency by prepending "\\RemoteComputerName", where RemoteComputerName is the name of the computer where the remote component resides, to the logical path in the wszOnLogicalPath parameter. The value of RemoteComputerName can be an IP address or a computer name returned by the GetComputerNameEx function.
If the remote component resides on a cluster, the writer must report the virtual name for the cluster, and it is the requester's responsibility to map the virtual name to the physical name of a cluster node before a volume shadow copy can be created.
To determine whether a dependency is local or remote, the requester must examine the component name returned in the pbstrComponentName parameter. If the component name begins with "\", the requester must assume that it specifies a remote dependency and that the first component following "\" is the RemoteComputerName that was specified by the writer. If the component name does not begin with "\", the requester should assume that it specifies a local dependency.
Windows Server 2003: This method cannot be used to declare remote dependencies until Windows Server 2003 with Service Pack 1 (SP1).
Requirements
Requirement | Value |
---|---|
Minimum supported client | Windows Vista [desktop apps only] |
Minimum supported server | Windows Server 2003 [desktop apps only] |
Target Platform | Windows |
Header | vswriter.h (include Vss.h, VsWriter.h) |
Library | VssApi.lib |