Thanks for creating this tool. It's been helpful as i learn my way around ZFS. Sometimes, being able to see things graphically is just better for learning and discovery compared to the CLI.

In any event, I wanted to be able to launch the tool from my desktop app launcher (KDE). I did not test on gnome, but the .desktop file should work.

When (for example) a dataset exists but a volume does not:

• the error is misleading,

no datasets available

Where a listing is empty, refer to something explanatory.

Volumes

zpoolconcepts(8) comes to mind however https://openzfs.github.io/openzfs-docs/man/8/zpoolconcepts.8.html appears to be outdated (compared to https://www.freebsd.org/cgi/man.cgi?query=zfsconcepts(8) for the same page for OpenZFS in FreeBSD) and unless I'm missing something, neither page effectively conceptualises a volume in the context of OpenZFS.

https://www.freebsd.org/cgi/man.cgi?query=zpool(8) no mention of volume or ZVOL.

Maybe this 2012 page: Aaron Toponce : ZFS Administration, Part XIV- ZVOLS

% sudo ./zyggy
grahamperrin's password:
sudo: unable to execute ./zyggy: No such file or directory
% ls -hl ./zyggy 
-rwxr-xr-x  1 grahamperrin  grahamperrin    19K 18 Jan 18:14 ./zyggy
% tail ./zyggy 
        dialog.set_title("GET ALL")
        dialog.set_default_size(800, 600)
        dialog.set_border_width(10)
        dialog.set_position(Gtk.WindowPosition.CENTER)
        dialog.show_all()


zyggy = App()

Gtk.main()% 
% date ; uname -v
Tue 19 Jan 2021 19:19:09 GMT
FreeBSD 13.0-CURRENT #75 main-c572-g82397d791: Sun Jan  3 20:00:09 GMT 2021     root@mowa219-gjp4-8570p:/usr/obj/usr/src/amd64.amd64/sys/GENERIC-NODEBUG 
% python --version
Python 3.7.9
%