PdhEnumObjectsA function (pdh.h)

Returns a list of objects available on the specified computer or in the specified log file.

To use handles to data sources, use the PdhEnumObjectsH function.

Syntax

PDH_FUNCTION PdhEnumObjectsA(
  [in]      LPCSTR  szDataSource,
  [in]      LPCSTR  szMachineName,
  [out]     PZZSTR  mszObjectList,
  [in, out] LPDWORD pcchBufferSize,
  [in]      DWORD   dwDetailLevel,
  [in]      BOOL    bRefresh
);

Parameters

[in] szDataSource

Null-terminated string that specifies the name of the log file used to enumerate the performance objects. If NULL, the function uses the computer specified in

the szMachineName parameter to enumerate the names.

[in] szMachineName

Null-terminated string that specifies the name of the computer used to enumerate the performance objects.

Include the leading slashes in the computer name, for example, \computername.

If the szDataSource parameter is NULL, you can set szMachineName to NULL to specify the local computer.

[out] mszObjectList

Caller-allocated buffer that receives the list of object names. Each object name in this list is terminated by a null character. The list is terminated with two null-terminator characters. Set to NULL if the pcchBufferLength parameter is zero.

[in, out] pcchBufferSize

Size of the mszObjectList buffer, in TCHARs. If zero on input, the function returns PDH_MORE_DATA and sets this parameter to the required buffer size. If the buffer is larger than the required size, the function sets this parameter to the actual size of the buffer that was used. If the specified size on input is greater than zero but less than the required size, you should not rely on the returned size to reallocate the buffer.

Windows XP:  Add one to the required buffer size.

[in] dwDetailLevel

Detail level of the performance items to return. All items that are of the specified detail level or less will be returned (the levels are listed in increasing order). This parameter can be one of the following values.

[in] bRefresh

Indicates if the cached object list should be automatically refreshed. Specify one of the following values.

If you call this function twice, once to get the size of the list and a second time to get the actual list, set this parameter to TRUE on the first call and FALSE on the second call. If both calls are TRUE, the second call may also return PDH_MORE_DATA because the object data may have changed between calls.

Return value

If the function succeeds, it returns ERROR_SUCCESS.

If the function fails, the return value is a system error code or a PDH error code. The following are possible values.

Remarks

You should call this function twice, the first time to get the required buffer size (set mszObjectList to NULL and pcchBufferLength to 0), and the second time to get the data.

Requirements

See also

PdhEnumObjectItems

PdhEnumObjectsH