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FsRtlMupGetProviderInfoFromFileObject function (ntifs.h)

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The FsRtlMupGetProviderInfoFromFileObject routine gets information about a network redirector that is registered with the multiple UNC provider (MUP) from a file object for a file that is located on a remote file system.

Syntax

NTSTATUS FsRtlMupGetProviderInfoFromFileObject(
  [in]      PFILE_OBJECT pFileObject,
  [in]      ULONG        Level,
  [out]     PVOID        pBuffer,
  [in, out] PULONG       pBufferSize
);

Parameters

[in] pFileObject

A pointer to a file object of a file that is located on a remote file system.

[in] Level

The level of information that is returned by the FsRtlMupGetProviderInfoFromFileObject routine. For more information about the possible values for this parameter, see the Remarks section.

[out] pBuffer

A pointer to a buffer that receives the information that is returned by the FsRtlMupGetProviderInfoFromFileObject routine. For more information about the format of the data that is returned in this buffer, see the Remarks section.

[in, out] pBufferSize

A pointer to a ULONG-typed variable that contains the size, in bytes, of the buffer that is pointed to by the pBuffer parameter. If the routine succeeds, this variable receives the size, in bytes, of data that is returned in the buffer.

Return value

The FsRtlMupGetProviderInfoFromFileObject routine returns one of the following NTSTATUS values.

Return code Description
STATUS_SUCCESS
 The information about the network redirector was successfully returned in the buffer that is pointed to by the pBuffer parameter.
STATUS_INVALID_PARAMETER
 One of the parameters was NULL or contained an invalid value.
STATUS_OBJECT_NAME_NOT_FOUND
 The file object that is pointed to by the pFileObject parameter does not correspond to a completely opened remote file system file object.
STATUS_BUFFER_TOO_SMALL
 The size of the buffer that is pointed to by the pBuffer parameter is too small to return any data. In this situation, the variable that is pointed to by the pBufferSize parameter receives the required size, in bytes, of the buffer.
STATUS_BUFFER_OVERFLOW
 The size of the buffer that is pointed to by the pBuffer parameter is too small to return all of the data. Only the data that would fit in the buffer was returned. In this situation, the variable that is pointed to by the pBufferSize parameter receives the required size, in bytes, of the buffer.

Remarks

A file system filter driver can call the FsRtlMupGetProviderInfoFromFileObject routine to get information about a network redirector from a file object for a file that is located on a remote file system. The amount of information that is returned by the FsRtlMupGetProviderInfoFromFileObject routine depends on the value of the Level parameter. If the Level parameter is set to 1, the FsRtlMupGetProviderInfoFromFileObject routine returns a FSRTL_MUP_PROVIDER_INFO_LEVEL_1 structure in the buffer that is pointed to by the pBuffer parameter. The FSRTL_MUP_PROVIDER_INFO_LEVEL_1 structure is defined as follows:

typedef struct _FSRTL_MUP_PROVIDER_INFO_LEVEL_1 {
  ULONG32  ProviderId;
} FSRTL_MUP_PROVIDER_INFO_LEVEL_1, *PFSRTL_MUP_PROVIDER_INFO_LEVEL_1;

If the Level parameter is set to 2, the FsRtlMupGetProviderInfoFromFileObject routine returns a FSRTL_MUP_PROVIDER_INFO_LEVEL_2 structure in the buffer that is pointed to by the pBuffer parameter. The FSRTL_MUP_PROVIDER_INFO_LEVEL_2 structure is defined as follows:

typedef struct _FSRTL_MUP_PROVIDER_INFO_LEVEL_2 {
  ULONG32  ProviderId;
  UNICODE_STRING  ProviderName;
} FSRTL_MUP_PROVIDER_INFO_LEVEL_2, *PFSRTL_MUP_PROVIDER_INFO_LEVEL_2;

A file system filter driver can quickly compare the value of the provider identifier to the value of other provider identifiers without needing to do a string comparison.

The value of the UNC provider identifier for a particular network redirector remains the same if the network redirector is unloaded from the system and then reloaded back into the system.

To get the UNC provider identifier of a network redirector from the device name of the network redirector, a file system filter driver can call the FsRtlMupGetProviderIdFromName routine.

Requirements

Requirement Value
Minimum supported client The FsRtlMupGetProviderInfoFromFileObject function is Windows Vista
Target Platform Universal
Header ntifs.h (include Ntifs.h)
Library NtosKrnl.lib
DLL NtosKrnl.exe
IRQL <= APC_LEVEL

See also

FsRtlMupGetProviderIdFromName