INF: Monitoring a Log File for an Event
PSS ID Number: Q105301
Article last modified on 07-27-1994

3.10

WINDOWS NT


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The information in this article applies to:

 - Microsoft Win32 Software Development Kit (SDK) for Windows NT
   version 3.1
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SUMMARY
=======

The following undocumented function is being exposed in order to provide a
temporary workaround for customers requiring this functionality. Microsoft
will provide an officially supported Win32 API which provides this
functionality in the next release.

As there are no guarantees that ElfChangeNotify() will be supported in all
future releases, we recommend that you rewrite your code to use the
supported Win32 API at the time that it becomes available.

MORE INFORMATION
================

To receive notification when something is written to the log file, use
the following undocumented application programming interface (API):

   UINT ElfChangeNotify( LogHandle, Event )
   HANDLE LogHandle,
   HANDLE Event

This function will cause the Event to be signaled when an event has
been written to the log file identified by the LogHandle.

   LogHandle
      Handle to a log file obtained from a call to OpenEventLog().

   Event
      A handle to a Win32 event.

Note that you must link with ADVAPI32.LIB.

Most of the ELF (Event Logging Facility) functions already have Win32
wrappers. ElfChangeNotify() does not have such a wrapper at this time,
but will have a wrapper in Windows NT 3.5, NotifyChangeEventLog(). It is
recommended that code that uses ElfChangeNotify() be rewritten to use
the new Win32 API, because ElfChangeNotify() may not be supported as
is in the future.

Additional reference words: 3.10 logfile
KBCategory: Prg
KBSubcategory: BseMisc

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Copyright Microsoft Corporation 1994.
