MD5 Checksum

Help & Support
1

Is there a 'button' to populate the 'MD5 Checksum' column ?
What I am looking for is something along the lines of
the 'Get Sizes' button but instead of Sizes, 'Get MD5' :slight_smile:

For some odd reason the MD5 Checksum column seems
to be blank for various files.

2

Hi gjandrews35,

The Dopus manual, page 179 may shed some light on this.
I havn't tried it yet, but I know it takes much time to calculate these.

From the Manual, page 179:

[quote]NOTE The MD5 Checksum column calculates and displays the MD5 checksum (hash value) of all files in the current folder. Because calculating the checksum may take a significant amount of time, it is disabled by default for files exceeding 5000kb in size. If you wish to increase this limit, set the following registry value to the desired limit in kilobytes (or set to 0 to have no limit at all):

HKEY_CURRENT_USER\Software\GPSoftware\Directory Opus\Config\User
(DWORD) MaxHashSize =
[/quote]
Regards,
:opusicon: porcupine

3

Yes that certainly sheds some light on the subject.
It is also a good incentive to have a 'Get MD5' button
instead or inconjunction with a 'self' populating column.

While registry hacks certainly are useful, it makes me
wonder why it is not in Settings/Preferences ?

4

I definitely think it would be a GREAT idea to have an explicit 'Get MD5sum' or MD5 argument to the 'Get Sizes' command that would NOT be subject to the internal file size limitation for the automatic calculation and display of MD5 values in the lister column...

Don't get me wrong - I STILL think that GPSoft is VERY wise to have a file size ceiling in it's automatic MD5 calculation and display feature, but an explicit command that a user would have to run to force the display of such information should not have the limit... this way, we could add the MD5 sum column to the lister, RETAIN the existing default file size limit to prevent performance from being devastated in folders with lots of big files, but be able to display the information for selected files on demand without having to edit the registry. Particularly since if I DID have a directory with 100 ISO files in it and want to see the MD5sum for just a few of them - going the registry way is non-specific and would calculate the MD5sum for ALL files in the folder... ouch.

5

I noticed these old threads on MD5 and figured I'd update them in case people find them by searching.

This command was added to Opus a while ago:

GetSizes NODESELECT MD5

If you run it with no files selected then it will calculate MD5 checksums for all files in the dir, or if you run it with some files selected then it'll only do the selected ones. Either way it ignores file size and will calculate the checksums of large files, unlike when you just add the MD5 column where large files will be skipped to avoid taking a long time and accessing the disk a lot.

You can use the registry to change the max size limit that is used when the column is added. See the bottom of page 179 in the PDF manual:

[quote]NOTE The MD5 Checksum column calculates and displays the MD5 checksum (hash value) of all files in the current folder. Because calculating the checksum may take a significant amount of time, it is disabled by default for files exceeding 5000kb in size. If you wish to increase this limit, set the following registry value to the desired limit in kilobytes (or set to 0 to have no limit at all):

HKEY_CURRENT_USER\Software\GPSoftware\Directory Opus\Config\User
(DWORD) MaxHashSize = [/quote]
The max size is probably worth keeping since you can run the GetSizes command above when you want to calculate MD5 for larger files.

There's also Clipboard COPYNAMES=hash and Clipboard COPYNAMES=hash2 for putting the filenames and their hashes into the clipboard. More on those can be found in the clipboard FAQ.

6

I tested that in one button...

<xml>
<button>
	<label>Get MD5 Hash</label>
	<tip>Gets MD5 Hash</tip>
	<icon1>34</icon1>
	<function>
		<instruction>GetSizes NODESELECT MD5</instruction>
		<instruction>Clipboard COPYNAMES=hash </instruction>
	</function>
</button>

and when i paste, it says no checksum available ... tried on file bigger than 5 MB.
v8.2.1.0

so it's not working for me. You have a working button?

7

Try updating to the latest version.