PerfQueryCounterData function (perflib.h)
Gets the values of the performance counters that match the counter specifications in the specified query.
Syntax
ULONG PerfQueryCounterData(
[in] HANDLE hQuery,
[out, optional] PPERF_DATA_HEADER pCounterBlock,
DWORD cbCounterBlock,
[out] LPDWORD pcbCounterBlockActual
);
Parameters
[in] hQuery
A handle to a query for the counter specifications of the performance counters for which you want to get the values.
[out, optional] pCounterBlock
A pointer to a buffer that has enough space to receive the amount of data that the cbCounterBlock parameter specifies, in bytes. May be NULL if
cbCounterBlock is 0.
cbCounterBlock
The size of the buffer that the pCounterBlock parameter specifies, in bytes.
[out] pcbCounterBlockActual
The size of the buffer actually required to get the performance counter values. The meaning depends on the value that the function
returns.
Function Return Value | Meaning of pcbCounterBlockActual |
---|---|
ERROR_SUCCESS | The number of
bytes of performance counter values that the function stored in the buffer that pCounterBlock specified. |
ERROR_NOT_ENOUGH_MEMORY | The
size of the buffer required to store the performance counter values, in bytes. Enlarge the buffer to the required size and call the function again. |
Other | The value is undefined and should not be used. |
Return value
Return code | Description |
---|---|
|
The function successfully stored all of the requested performance counter values in the buffer that pCounterBlock specified. The value that pcbCounterBlockActual points to indicates amount of information actually stored in the buffer, in bytes. |
|
The buffer that pCounterBlock specified was not large enough to store all of the requested performance counter values. The value that pcbCounterBlockActual points to indicates the size of the buffer required to store all of the information. Enlarge the buffer to the required
size and call the function again. |
For other types of failures, the return value is a system error code.
Remarks
The information about the performance counter values is written to the buffer that pCounterBlock specifies as a PERF_DATA_HEADER block, which consists PERF_DATA_HEADER structure followed by a sequence of PERF_COUNTER_HEADER blocks.
Requirements
Requirement | Value |
---|---|
Minimum supported client | Windows 10, version 1607 [desktop apps only] |
Minimum supported server | Windows Server 2016 [desktop apps only] |
Target Platform | Windows |
Header | perflib.h |
Library | AdvAPI32.lib |
DLL | AdvAPI32.dll |