HvRetrieveDebugData function

The HvRetrieveDebugData function retrieves available data that is received on a debugging connection.

Syntax

HV_STATUS  HvRetrieveDebugData(
  _In_   PUINT32 Count,
  _In_   HV_DEBUG_OPTIONS Options,
  _In_   HV_NANO100_TIME Timeout,
  _Out_  PUINT32 RetrievedCount,
  _In_   PUINT32 RemainingCount,
  _Out_  PUINT8 Data
);

Parameters

Count [in]

A pointer to a variable that contains the number of bytes that HvRetrieveDebugData should retrieve and put into the buffer to which the Data parameter points. This number can range from zero to HV_DEBUG_MAXIMUM_DATA_SIZE. HvRetrieveDebugData returns the actual number of bytes that it retrieved and put into the buffer.

Options [in]

A valid bitwise OR combination of HV_DEBUG_OPTIONS values that specify the retrieving options.

The HV_DEBUG_RETRIEVE_LOOP option indicates that if there is no immediately available data, the hypervisor should suspend the virtual processor for the interval that the Timeout parameter specifies.

The HV_DEBUG_RETRIEVE_TEST_ACTIVITY option indicates that if no receive activity (for any session) has occurred on the physical connection since the last HvRetrieveDebugData hypercall, an error should be returned to the caller. HvRetrieveDebugData performs this test before all other processing.

Timeout [in]

The maximum time, in 100 nanosecond units, that the hypervisor should suspend the virtual processor while waiting for data to arrive.

RetrievedCount [out]

A pointer to a variable that HvRetrieveDebugData fills with the number of bytes that HvRetrieveDebugData returned in the buffer to which Data points.

RemainingCount [in]

A pointer to a variable that HvRetrieveDebugData fills with the number of bytes in the buffer that Data points to that are pending retrieval, after HvRetrieveDebugData returns the number of bytes to which the Count parameter points.

Data [out]

A pointer to a buffer that HvRetrieveDebugData fills with the bytes received from the beginning of the session for the data stream connection.

Return value

HvRetrieveDebugData returns one of the following values. In addition to these values, HvRetrieveDebugData can also return one of the values that are specified in Common Hypercall Status Codes.

Remarks

HvRetrieveDebugData retrieves up to HV_DEBUG_MAXIMUM_DATA_SIZE bytes from the session's received data stream. If no data is available, HvRetrieveDebugData returns HV_STATUS_NO_DATA. A caller can set the variable to which the Count parameter points to zero to determine whether any received data is present in the incoming session buffer. If data is present, HvRetrieveDebugData returns HV_STATUS_SUCCESS but does not return any data.

HvRetrieveDebugData has the following restrictions:

• The partition must possess the Debugging privilege.

Native Interface

Requirements

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Build date: 11/16/2013