2.2.4.8 _PERF_COUNTER_HEADER

The _PERF_COUNTER_HEADER structure is used at the beginning of a counter header block.

 typedef struct _PERF_COUNTER_HEADER {
   unsigned long dwStatus;
   unsigned long dwType;
   unsigned long dwSize;
   unsigned long Reserved;
 } PERF_COUNTER_HEADER,
  *PPERFCOUNTERHEADER;

dwStatus: A Win32 error code that indicates whether the operation was successful. Win32 error codes are specified in [MS-ERREF].

dwType: The performance counter type. The value MUST be one of the following.

Value	Meaning
PERF_ERROR_RETURN 0x00000000	An error occurred when the performance counter value was queried.
PERF_SINGLE_COUNTER 0x00000001	The query returned a single-instance performance counter value.
PERF_MULTI_COUNTERS 0x00000002	The query returned multiple performance counter values.
PERF_MULTI_INSTANCES 0x00000004	The query returned values from multiple instances of a performance counter.
PERF_COUNTERSET 0x00000006	The query returned the values of all instances of all performance counters that belong to the counterset.

dwSize: The size, in bytes, of the structure and data.

Reserved: MUST be set to 0, and MUST be ignored on receipt.