epubcheck plugin for Sigil - Page 38

DiapDealer · 01-16-2026, 06:23 AM

I'm happy it's working for you now, but there is really no need to install Python. Sigil comes with its own bundled Python environment.

B10Mediaworx · 01-16-2026, 12:01 PM

Yes, I knew that, and I've always had the "use bundled python" checked, which was why I couldn't figure out what changed and why it was no longer working.

DiapDealer · 01-17-2026, 10:52 AM

I got the exact same error as you on my virtual Windows 10 machine when launching the EPubCheck plugin. It then began to work correctly with no changes made whatsoever. I suspect something else is going on that triggers the failure under the right conditions.

phillipgessert · 01-17-2026, 02:56 PM

Probably unrelated, but I started getting an error re: missing distutils when using this plugin on MacOS. I thought it was an issue with the Mac’s python version, so was surprised to see I already had the Sigil python bundle checked. When I unchecked it, the plugin worked again.

Doitsu · 01-17-2026, 03:17 PM

Quote:

Originally Posted by phillipgessert

Probably unrelated, but I started getting an error re: missing distutils when using this plugin on MacOS. I thought it was an issue with the Mac’s python version, so was surprised to see I already had the Sigil python bundle checked. When I unchecked it, the plugin worked again.

An older plugin version used pkg_resources for parsing version numbers.
Please check pugin.py for the following import:

Code:

from pkg_resources import parse_version

If it's not commented out you're using an older plugin version.

KevinH · 01-17-2026, 03:19 PM

And fwiw, according to Google:

Quote:

The distutils package was the original standard library module in Python for building and installing other Python modules and extensions. However, it has been deprecated since Python 3.10 and was completely removed in Python 3.12 in favor of modern packaging tools like setuptools.

So the bundled Python for Mac and Windows is version 3.13 and will not have distutils.

DiapDealer · 01-17-2026, 03:50 PM

That IS strange. The bundled Python is checked by default on new Windows, macOS, and Linux AppImage installations. So if nobody ever unchecks the box, they will be using the bundled Python (even after updates. What's surprising is that I've never heard of Sigil's bundled Python throwing distutils errors on macOS--with ANY plugin. You should not have to uncheck the Use Bundled Python setting to get the epubcheck plugin to work on maOS.

EDIT: Never mind, it looks like I took too long to prepare my post. Doitsu's post has probably nailed the issue/solution.

phillipgessert · 01-17-2026, 04:03 PM

I'll update my version! Classic mistake.

Doitsu · 09-18-2026, 12:47 PM

FYI: in the latest EPUBCheck release, the devs have added a new parameter that'll output all messages: --maxOfEachMessage

If you want to test this new parameter, open plugin.py search for:

Code:

    # display status message

and change it to:

Code:

    args.extend(['--maxOfEachMessage', 'unlimited'])

    # display status message

(There need to be exactly 4 spaces before the new line.)

You can test it with this epub file.

Without the new parameter the plugin will output 71 messages. After adding the additional line, it'll output 3435 messages.

01-17-2026, 02:56 PM	#559
phillipgessert Addict Posts: 332 Karma: 3200122 Join Date: Oct 2015 Location: Madison, WI Device: Kindle 5th Gen	Probably unrelated, but I started getting an error re: missing distutils when using this plugin on MacOS. I thought it was an issue with the Mac’s python version, so was surprised to see I already had the Sigil python bundle checked. When I unchecked it, the plugin worked again. Last edited by phillipgessert; 01-17-2026 at 02:59 PM.

01-17-2026, 03:50 PM	#562
DiapDealer Grand Sorcerer Posts: 29,779 Karma: 212614993 Join Date: Jan 2010 Device: Nexus 7, Kindle Fire HD	That IS strange. The bundled Python is checked by default on new Windows, macOS, and Linux AppImage installations. So if nobody ever unchecks the box, they will be using the bundled Python (even after updates. What's surprising is that I've never heard of Sigil's bundled Python throwing distutils errors on macOS--with ANY plugin. You should not have to uncheck the Use Bundled Python setting to get the epubcheck plugin to work on maOS. EDIT: Never mind, it looks like I took too long to prepare my post. Doitsu's post has probably nailed the issue/solution. Last edited by DiapDealer; 01-17-2026 at 03:52 PM.

09-18-2026, 12:47 PM	#564
Doitsu Grand Sorcerer Posts: 5,924 Karma: 24259515 Join Date: Dec 2010 Device: Kindle PW2	FYI: in the latest EPUBCheck release, the devs have added a new parameter that'll output *all* messages: --maxOfEachMessage If you want to test this new parameter, open plugin.py search for: Code: # display status message and change it to: Code: args.extend(['--maxOfEachMessage', 'unlimited']) # display status message (There need to be exactly 4 spaces before the new line.) You can test it with this epub file. Without the new parameter the plugin will output 71 messages. After adding the additional line, it'll output 3435 messages.

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01-16-2026, 06:23 AM	#556
DiapDealer Grand Sorcerer Posts: 29,779 Karma: 212614993 Join Date: Jan 2010 Device: Nexus 7, Kindle Fire HD	I'm happy it's working for you now, but there is really no need to install Python. Sigil comes with its own bundled Python environment.

01-16-2026, 12:01 PM	#557
B10Mediaworx Elizabeth Beeton Posts: 5 Karma: 100000 Join Date: May 2008 Location: Kansas City, MO Device: iPad, Galaxy S22, Paperwhite, eBookWise-1150	Yes, I knew that, and I've always had the "use bundled python" checked, which was why I couldn't figure out what changed and why it was no longer working.

01-17-2026, 10:52 AM	#558
DiapDealer Grand Sorcerer Posts: 29,779 Karma: 212614993 Join Date: Jan 2010 Device: Nexus 7, Kindle Fire HD	I got the exact same error as you on my virtual Windows 10 machine when launching the EPubCheck plugin. It then began to work correctly with no changes made whatsoever. I suspect something else is going on that triggers the failure under the right conditions.

01-17-2026, 04:03 PM	#563
phillipgessert Addict Posts: 332 Karma: 3200122 Join Date: Oct 2015 Location: Madison, WI Device: Kindle 5th Gen	I'll update my version! Classic mistake.