NdisMWriteLogData (NDIS 5.1) function

Note   NDIS 5. x has been deprecated and is superseded by NDIS 6. x. For new NDIS driver development, see Network Drivers Starting with Windows Vista. For information about porting NDIS 5. x drivers to NDIS 6. x, see Porting NDIS 5.x Drivers to NDIS 6.0.

NdisMWriteLogData transfers driver-supplied information into the log file for consumption and display by a driver-dedicated Win32 application.


NDIS_STATUS NdisMWriteLogData(
  _In_  NDIS_HANDLE LogHandle,
  _In_  PVOID LogBuffer,
  _In_  UINT LogBufferSize


LogHandle [in]

Specifies the handle returned by NdisMCreateLog.

LogBuffer [in]

Pointer to a driver-allocated buffer containing the information to be written.

LogBufferSize [in]

Specifies how many bytes of data to copy into the log file.

Return value

NdisMWriteLogData can return one of the following:

Return codeDescription

The driver-supplied data at LogBuffer has been copied into the log file.


The given LogBufferSize is too large, that is, larger than the log file itself.



If the driver-dedicated application has an outstanding request for log file data, NdisMWriteLogData satisfies that request as soon as it has copied the driver-supplied information into the log file.

The miniport driver can supply a LogBuffer pointer to a location on the kernel stack if it is currently running at IRQL < DISPATCH_LEVEL. Otherwise, LogBuffer must access a buffer that the driver allocated from nonpaged pool.

The driver must release any spin lock it is holding before calling NdisMWriteLogData.

NdisMWriteLogData does not recognize boundaries between log records, nor does the Win32 function, DeviceIoControl, which applications can call with IOCTL_NDIS_GET_LOG_DATA to retrieve data written to an NDIS log file by an NDIS NIC driver. NdisMWriteLogData writes all miniport driver-supplied data at LogBuffer into the log file as a byte stream. DeviceIoControl reads the data from such a log as a byte stream, as well.

Consequently, an application reading an NDIS log must collect retrieved data into records. To aid such an application in collecting variable-length records, any miniport driver writing to such a log can insert a marker at the beginning of each record. Then, the application formatting the retrieved data can search for these markers to determine the start of each record.



See NdisMWriteLogData.


Ndis.h (include Ndis.h)



See also




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