|
List Info
Thread: How to unlock file
|
|
| How to unlock file |
|
2006-04-04 10:01:01 |
|
Hi Jarek,
unlocking a locked file is not supported by any operating system.
When an application locks a file for access (ie. write) it protects itself from modifications made
by other applications. The OS guarantees, that this will work as assumed.
If you need to open a file which is opened by another app. try to open it as read-only and/or use
an appropiate share-mode (deny none). Have a look into delphi's help for "FileOpen".
Have fun
Bob
> ; I need to force unlock file open by other applicaton. Can you suggest
> any idea how to do this?
>;
> ; ; Jarek
|
| How to unlock file |
|
2006-04-04 10:35:52 |
|
Hi Bob
you are right in that sense that it isn't oficially supported.
Nevertheless it is possible - lets have a look at
http://ccollomb.free.fr/unlocker/ or
http://sourceforge.net/project/showfiles.php?group_id=151239. But how it
is done ?
; ; Jarek
j.meier jmeiersoftware.de wrote
>; Hi Jarek,
> unlocking a locked file is not supported by any operating system.
> When an application locks a file for access (ie. write) it protects
> itself from modifications made
> by other applications. The OS guarantees, that this will work as assumed.
> If you need to open a file which is opened by another app. try to open
> it as read-only and/or use
> an appropiate share-mode (deny none). Have a look into delphi's help
> for "FileOpen".
> Have fun
> Bob
>
> > ; I need to force unlock file open by other applicaton. Can you
> suggest
> > ; any idea how to do this?
>; > ;
> > ; ; ; Jarek
>;
>
>
> -----------------------------------------------------
> Home page: http://groups.yahoo.com/group/delphi-en/
> To unsubscribe: delphi-en-unsubscribe@yahoogroups.com
>
>
>; ------------------------------------------------------------------------
> YAHOO! GROUPS LINKS
>;
> * Visit your group "delphi-en
> ; <http://groups.yahoo.com/group/delphi-en>;" on the web.
> ;
> * To unsubscribe from this group, send an email to:
> ; delphi-en-unsubscribe@yahoogroups.com
> ; <mailto:delphi-en-unsubscribe@yahoogroups.com?subject=Unsubscribe>
>
> * Your use of Yahoo! Groups is subject to the Yahoo! Terms of
> ; Service <http://docs.yahoo.com/info/terms/>.
>
>
> ------------------------------------------------------------------------
>
>
>
> __________ NOD32 Informacje 1.1469 (20060404) __________
>
>; Wiadomosc zostala sprawdzona przez System Antywirusowy NOD32
>; http://www.nod32.com lub http://www.nod32.pl
|
| How to unlock file |
|
2006-04-04 10:51:58 |
|
Well, obviously, you could have a glimpse on the sourcecode of the
SourceForge-based project, now couldn't you? 
Cheers
Mike
;
___________________________________________________________
Yahoo! Photos – NEW, now offering a quality print service from just 8p a photo http://uk.photos.yahoo.com
|
| How to unlock file |
|
2006-04-04 11:43:08 |
|
I've seek sourceforge in the hope to find something but yhe problem is
that DeleteFileLock project on sourcrforge is only as windows exe :-(
; ; Jarek
Michał Woźniak wrote:
> Well, obviously, you could have a glimpse on the sourcecode of the
> SourceForge-based project, now couldn't you?
>
> Cheers
> Mike
>
> ;
> ___________________________________________________________
> Yahoo! Photos � NEW, now offering a quality print service from just 8p
> a photo http://uk.photos.yahoo.com
>;
>
> -----------------------------------------------------
> Home page: http://groups.yahoo.com/group/delphi-en/
> To unsubscribe: delphi-en-unsubscribe@yahoogroups.com
>
>
>; ------------------------------------------------------------------------
> YAHOO! GROUPS LINKS
>;
> * Visit your group "delphi-en
> ; <http://groups.yahoo.com/group/delphi-en>;" on the web.
> ;
> * To unsubscribe from this group, send an email to:
> ; delphi-en-unsubscribe@yahoogroups.com
> ; <mailto:delphi-en-unsubscribe@yahoogroups.com?subject=Unsubscribe>
>
> * Your use of Yahoo! Groups is subject to the Yahoo! Terms of
> ; Service <http://docs.yahoo.com/info/terms/>.
>
>
> ------------------------------------------------------------------------
>
>
>
> __________ NOD32 Informacje 1.1469 (20060404) __________
>
>; Wiadomosc zostala sprawdzona przez System Antywirusowy NOD32
>; http://www.nod32.com lub http://www.nod32.pl
|
| How to unlock file |
|
2006-04-04 14:30:35 |
|
Duży Królik wrote:
> Hi Bob
> you are right in that sense that it isn't oficially supported.
> Nevertheless it is possible - lets have a look at
> http://ccollomb.free.fr/unlocker/ or
> http://sourceforge.net/project/showfiles.php?group_id=151239. But how it
> is done ?
>
> ; ; Jarek
Well, I can think of several ways:
1) Get direct access to the table of all file handles in the system.
Requires kernel-mode privileges. And lots of "hand waving".
2) Inject a small bit of executable code into another process' space
using CreateRemoteThread() and related kin. Once inside the process
space, execute CloseHandle() on the desired handle. You can probably
enumerate another process' file handles without injecting anything.
3) Inject a kernel API monitor (hooks API calls) and watch all calls to
and from the kernel. Then attempt to replicate the procedure and pull
lots of hair out trying to figure out what went wrong. Best to use this
approach with a program that has had most of the bugs stamped out of it:
http://www.sysinternals.com/Utilities/ProcessExplorer.html
Ran a quick Google search and came up with this (very hacky) partial
solution:
http://vmsone.com/~decuslib/vmssig/vmslt97a/ntstuff/enumhand.txt
If you don't mind a full solution being NT-only (i.e. not Win9x/Me), you
can combine the above partial solution with this:
http://www.codeguru.com/Cpp/W-P/files/fileio/article.php/c1287/
IMPORTANT: The first link depends on the Windows DDK, which can be
obtained for free via slightly questionable means (KMDF):
http://www.microsoft.com/whdc/driver/wdf/KMDF.mspx
http://download.microsoft.com/download/3/b/5/3b519887-c4af-4ab3-9578-cec48cc84d94/WDFv10.iso
(Usually you have to pay for the [Server 2003 SP1] DDK. Second link is
a direct download link to the 263MB ISO image).
--
Thomas Hruska
CubicleSoft President
Ph: 517-803-4197
Safe C++ Design Principles (First Edition)
Learn how to write memory leak-free, secure,
portable, and user-friendly software.
Learn more and view a sample chapter:
http://www.CubicleSoft.com/SafeCPPDesign/
|
[1-5]
|
|
|
about | contact Other archives ( Real Estate discussion Medical topics )
|