Duplicate File Finder (ability to note symbolic links)

The duplicate file finder included in CCleaner v4.0 does not properly handle symbolic links, and reports the contents of a symlink as being a duplicate of itself

Eg.

C:\Program Files\Steam is symlinked to F:\Games\Steam

CCleaner reports every file in each folder as being a duplicate.

Thanks, we'll look into this.

title edited to stave off unrelated me-too's

Desperate Plea to Mr. T.

When you add distinction between the link and its contents for the duplicate finder,

PLEASE do not make any such distinction for the normal cleaning of junk files.

I make extensive use of Reparse points so that things such as my Palemoon (Firefox) browser profiles which really exist in D:\ only APPEAR to be held on C:\.

I am very happy that CCleaner still cleans the browser caches as though they were on C:\.

I hope it will continue to do so.

SUGGESTION

Use the "search" capability employed by Defraggler which distinguishes between the source and destination of a hard link.

Defraggler knows that there are only TWO instances of CMD.EXE held in C:\Windows

cmd.exe 1 345088 C:\Windows\System32\
cmd.exe 1 302592 C:\Windows\winsxs\wow64_microsoft-windows-commandprompt_31bf3856ad364e35_6.1.7601.17514_none_f387767e655cd5ab\

Other tools such as Windows Explorer and Locate32 see FOUR instances because they cannot distinguish between the reality and the shadow of a hard link,

as I have shown in

http://forum.pirifor...showtopic=38203

cmd 337 KB 21/11/2010 03:23 C:\Windows\System32
cmd 337 KB 21/11/2010 03:23 C:\Windows\winsxs\amd64_microsoftwindowscommandprompt_31bf3856ad364e35_6.1.7601.17514_none_e932cc2c30fc13b0
cmd 296 KB 21/11/2010 03:24 C:\Windows\SysWOW64
cmd 296 KB 21/11/2010 03:24 C:\Windows\winsxs\wow64_microsoft-windowscommandprompt_31bf3856ad364e35_6.1.7601.17514_none_f387767e655cd5ab

Hi Alan_B

Don't worry, we will only do such distinction when finding for duplicates.

Take care

Thanks Mr. T.

Previously I only looked at WinSXS / System32 hard-link problems

I have now looked at duplicates in general.

When I deselect all drives other than C:\ the default result is

19 pairs of duplicates on C:\.

15 pairs are very important to Comodo Internet Security suite and hopefully that is self-protecting.

4 pairs are very important to actually booting up Windows 7 :-

1 pair is C:\Boot\...\Boot.sdi

3 pairs are C:\boot\...\fonts\???_boot.ttf

It appears to me that removing such duplicates could have significant consequences.

Unfortunately some users will blindly trust CCleaner's actions regardless,

and will Wipe Free space because they think it will give more free space.

By unchecking System and Read Only and Hidden check-boxes another 9 pairs.

Many of these appear to be some sort of reparse point, e.g.

C:\ProgramData\Microsoft\Network\Downloader\qmgr1.dat

C:\Users\All Users\Microsoft\Network\Downloader\qmgr1.dat

Both instances are seen by Windows EXplorer as

4.00 MB (4,194,304 bytes) Modified 27 March 2013, 11:51:11

I searched C:\ for qmgr1.dat using Defraggler version 2.13.

It found the real deal at

C:\ProgramData\Microsoft\Network\Downloader\qmgr1.dat

Quite obviously,

depending upon Access Control Levels which Windows can fumble and users can meddle with,

deleting either the real deal file or the counterfeit shadow could destroy both reality and illusion.

If I additionally uncheck the "File Size Under" box it takes much longer to search and produces many results.

It is worth noting that partitions other than C:\ are commonly used for valuable libraries and archives,

and are not always protected as being hidden or system or Read Only,

therefore if Reparse Points provide alternative Reality and Illusion paths the removal of either duplicate could destroy both.

MY CONCLUSIONS :-

It is essential that all reparse-points and hard-links be excluded from any list of "duplicates".

I agree with other commentators that a checksum must be available to determine if files with the same name are really the same.

I think SHA-512 is valuable to defeat skilled malware creators who can infect a download and manipulate its MD5 hash checksum.

but SHA-512 could be overkill for simply deciding whether the user has duplicated a download,

and perhaps a simple CCRC would suffice.

Checksum validation should have a separate check box.

If the user can uncheck the "size" box to see if he has more than one quality of an MP4 download,

He would also need to avoid hash checksum validation.

Regards

Alan

Al, thanks for your input. I imagine no gain by eliminating dupe files, so do you feel it's worth the risk? Better we not fix something that ain't broke?

Although strictly in lay terms, allow me to relate my experience. I updated to the new version earlier this week. I was most curious how effective the dupe cleaner was so I used it. The next day or so the PC experienced BSOD. I built this PC in May and have never had a serious issue. From safe mode I just used W7s System Restore and all was good. I never associated it with the dupe cleaner so I re-installed CC and tried the dupe cleaner again. After lunch today I woke the x64 W7 SP1 PC from Sleep and my 120gb SSD had gone from 87gbs of free space to a few MBs. I now suspected it had something to do with the duplicate cleaner, of course I still don't know for sure. I restored from my weekly Paragon image I made Saturday (I also image with W7s backup which is very good too.) and every thing is back to normal! Also, why doesn't Cyberfox's spell check work here? That is kind of dangerous for me. lol

People will need to be informed and instructed that operating a duplicate finder and remover program is an operation that requires 100% manual review and knowledge of precisely what is being removed.

Especially considering that the rest of CCleaner is "automated" and has "safe" default settings which work correctly. This methodology will instill a false confidence in newcomers and the result is anything from a few missing icons to BSOD requiring a restore operation and a bad taste against Piriform.

It will do no good (and plenty of bad) to have novices getting click-happy in the dupefinder area thinking they're freeing up tons of space. And all the while unwittingly castrating a working o/s file-by-file.

Typically a user that has advanced enough on their own will sooner or later seek out a dupe remover utility and be quite aware of the pitfalls and dangers associated with it. Luckily the above user had a backup from which to restore.

And not only that I ran the finder and it reported 8 DESKTOP.INI files as being the same, but in reality are different. It is known to us expert regulars on the forum that no contents comparison is being done. But who else going to know that?

I only post this for the benefit of newcomers. I'm done.

[grumpy-rant]

I love how everyone's like "oh look these are all duplicates let trash everything!"

READ MY SIGNATURE, REPLACE WORD REGISTRY WITH DUPLICaTES

stop causing havoc with your PCs just cAuse you're too lazy to read the darned results!

[/grumpy-rant]

please everyone take some personal responsibility.

**slinks back into cave grumbling about how 'yet another fan fav "we must have it" feature was added, even though good reason for not including it was presented' and 'then what was said will come about from it happens and everyone moans'

[grumpy-rant]

I love how everyone's like "oh look these are all duplicates let trash everything!"

READ MY SIGNATURE, REPLACE WORD REGISTRY WITH DUPLICaTES

stop causing havoc with your PCs just cAuse you're too lazy to read the darned results!

[/grumpy-rant]

please everyone take some personal responsibility.

**slinks back into cave grumbling about how 'yet another fan fav "we must have it" feature was added, even though good reason for not including it was presented' and 'then what was said will come about from it happens and everyone moans'

I think one of your capital a's swapped places with a lower case one.

I think one of your capital a's swapped places with a lower case one.

it's this darn typewriter I wish we wiz still usin' good old fashioned stone on clay

use duplicate file deleter this is simply the best

Welcome to this forum BUT

A suggestion of an "alternative" third party tool of unknown origin is not really relevant to software that has advanced 16 versions since this bug report.

And Goodbye from this forum, as he, or possibly she, has an entry in the spammers' hall of infamy.