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Q172710: How to Use the OH Tool on the Windows NT 4.0 Resource Kit

Article: Q172710
Product(s): Microsoft Windows NT
Version(s): WinNT:4.0
Operating System(s): 
Keyword(s): kbtool
Last Modified: 09-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Workstation version 4.0 
- Microsoft Windows NT Server version 4.0 
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SUMMARY
=======

This article discusses the OH monitoring tool OH (Oh.exe) that is included in
the Microsoft Windows NT Server 4.0 Resource Kit Supplement Two. The OH utility
can help monitor which files, registry keys, and directories are in use by
certain services at any given time.

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

This command-line tool shows the handles of all open windows. Alternatively, you
can constrain the OH display to show only information relating to a particular
process, object type, or object name. This feature is useful when a sharing
violation occurs because you can find the process that has a file open at the
time of violation.

To function properly, OH requires that an option internal to the Windows NT
kernel be enabled. This option maintains a linked list of all objects by object
type. If OH detects that this option is not set, OH sets it and sends a message
that the user must restart the computer before the option will take effect.
After restarting, OH can give useful results.

This linked list costs 8 bytes of overhead for each object. If desired, this
option can later be disabled with Gflags.exe (in the Windows NT 4.0 Resource
Kit) by clearing the check box for" Maintain a list of objects for each type" in
the Global Flags window, then restarting the system.

The most convenient way to use OH is to have it pipe the data to a text file. At
the command prompt type:

  Oh >***.txt {where *** is the name you provide}

To view the data, open the file with Notepad.

REFERENCES
==========

For additional information about the OH utility, type the following line at a
command prompt type, and then press ENTER:

  Use OH /?

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Keywords          : kbtool 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : WinNT:4.0
Issue type        : kbinfo

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