WmiTraceMessageVa function (wdm.h)
The WmiTraceMessageVa routine adds a message to the output log of a WPP software tracing session.
Syntax
NTSTATUS WmiTraceMessageVa(
[in] TRACELOGGER_HANDLE LoggerHandle,
[in] ULONG MessageFlags,
[in] LPCGUID MessageGuid,
[in] USHORT MessageNumber,
[in] va_list MessageArgList
);
Parameters
[in] LoggerHandle
Specifies a trace handle for a software tracing session.
[in] MessageFlags
Specifies a bitwise OR of one or more message flags. See the Remarks section for details.
[in] MessageGuid
Specifies a GUID that identifies a software trace class.
[in] MessageNumber
Identifies the message subtype. The meaning of subtypes is specific to the software trace class and the provider.
[in] MessageArgList
Provides a required list of message parameters that specify a set of message parts. The parameters are organized as a sequence of parameter pairs, where each pair specifies one part of the complete message. Each parameter pair consists of a PVOID pointer to data, followed immediately by a ULONG value that specifies the length of the data. The parameter list must be terminated by a NULL PVOID pointer followed by a ULONG(0).
Return value
WmiTraceMessageVa returns one of the following values:
Return code | Description |
---|---|
|
The operation completed successfully. |
|
LoggerHandle is not a valid software trace handle. |
|
There is insufficient buffer memory to log the message. See the Remarks section for more information. |
|
An internal error occurred. |
Remarks
A caller can use WmiTraceMessage or WmiTraceMessageVa to add a message to the output log of a WPP software tracing session. WmiTraceMessage simplifies a caller's code by handling the variable list mechanism before calling WmiTraceMessageVa.
A caller can set the following message flags:
Flag | Description |
---|---|
TRACE_MESSAGE_SEQUENCE | Include a sequence number in the message. Message sequencing can only be used if it is enabled for the software tracing session specified by LoggerHandle. |
TRACE_MESSAGE_GUID | MessageGuid specifies a GUID that identifies a software trace class. This flag must be set. |
TRACE_MESSAGE_TIMESTAMP | Include a time stamp in the message. |
TRACE_MESSAGE_PERFORMANCE_TIMESTAMP | This flag is not implemented and is obsolete. It must not be used. |
TRACE_MESSAGE_SYSTEMINFO | Include the thread identifier (TID) and process identifier (PID) in the message. |
WmiTraceMessageVa does not log the message if one of the following is true:
- The total size, in bytes, of the message data and the message header is greater than the size of individual message buffers allocated for a software tracing session. (The maximum message header size is 48 bytes.)
- All message buffers allocated to software tracing session are full.
Requirements
Requirement | Value |
---|---|
Minimum supported client | Available in Windows XP and later versions of Windows. |
Target Platform | Universal |
Header | wdm.h (include Wdm.h, Ntddk.h, Ntifs.h) |
Library | NtosKrnl.lib |
DLL | NtosKrnl.exe |
IRQL | See Remarks section. |