CEL_HEADER

  • Article

This structure precedes every logged event that is sent out through the logging mechanism.

typedef struct __CEL_HEADER {
  DWORD Length:16;
  DWORD ID:14;
  DWORD Reserved:1;
  DWORD fTimeStamp:1;
} CEL_HEADER, *PCEL_HEADER;

Members

  • Length
    The lower 16 bits of the header holds the length, in bytes, of the event structure. This does not include the length of the header structure or the time stamp if it is present.
  • ID
    The next 14 bits of the header are used for the event identifier.
  • Reserved
    This bit is reserved for future use.
  • fTimeStamp
    The upper bit of the header is used to indicate whether or not a time stamp is present. If this bit is set, a 32-bit time stamp follows the structure and the value is given in tick counts. Otherwise, no time stamp follows.

Remarks

This structure is a single DWORD broken into several sections; it will be followed by a DWORD time stamp if the appropriate flag is set.

If you replace the event-tracking engine (Celog.lib) with your own, you should follow the same rules and include CEL_HEADER with each event. CEL_HEADER is attached to the data by CeLogData.

The format of the header has two forms depending on whether the event is a flagged event or not.

The following table shows the format of the non-flagged event header.

Data Description
T Flag that indicates whether TIMESTAMP is added to the header (fTimeStamp)
TIMESTAMP Time that an event was recorded
ID Event that occurred (ID)
LEN Length of the data (Length)
DATA Raw data that follows the header

The following table shows the format of the flagged event header.

Data Description
T Flag that indicates whether TIMESTAMP is added to the header (fTimeStamp)
CELID_FLAGGED Identifier that is used to determine whether the event has been flagged and the structure changed
TIMESTAMP Time that an event was recorded
ID Event that occurred (ID)
FLAG User-provided flag use to flag the event
LEN Length of the data (Length)
DATA Raw data that follows the header

Requirements

OS Versions: Windows CE 3.0 and later.
Header: Celog.h.

See Also

CeLogData

Last updated on Wednesday, April 13, 2005

© 2005 Microsoft Corporation. All rights reserved.