PdhOpenQuery

The PdhOpenQuery function creates and initializes a unique query structure that is used to manage collection of performance data.

PDH_STATUS PdhOpenQuery(
  IN LPVOID pReserved,  // reserved
  IN DWORD dwUserData,  // a value associated with this query
  IN HQUERY *phQuery    // pointer to a buffer that will receive the 
                        // query handle
);
 

Parameters

pReserved

Reserved. Must be NULL.

dwUserData

A user-defined DWORD value that is to be associated with this query. You can call PdhGetCounterInfo to retrieve the user data value for the query in which a counter resides.

phQuery

A pointer to the buffer to receive the handle to the query that is created.

Return Values

If the function succeeds, it returns ERROR_SUCCESS, creates a new query, and returns the handle to the query in the buffer pointed to by phQuery.

If the function fails, the return value is a PDH error status defined in pdhmsg.h. The following are possible error values:

PDH_INVALID_ARGUMENT

One or more arguments are invalid.

PDH_MEMORY_ALLOCATION_FAILURE

A memory buffer could not be allocated.

See Also

Performance Data Helper Overview, Performance Data Functions, , PdhCloseQuery, PdhGetCounterInfo