Zfs: ZFS snapshots between midnight and 1 AM are missing a padded zero in the creation propery

[darkpixel]

System information

Distribution Name | Proxmox
Distribution Version |
Linux Kernel | 5.3.10-1-pve
Architecture | x86_64
ZFS Version | 0.8.2-pve2
SPL Version | 0.8.2-pve2

Describe the problem you're observing

The creation property on snapshots is missing the trailing zero when the hour is midnight.

Describe how to reproduce the problem

zfs create tank/users
Between 00:00 and 00:59 hours, do:

zfs snapshot tank/users@mysnapshot
zfs get creation -o value -H tank/users@mysnapshot
Tue Feb 25  0:06 2020

Notice the hours are 0:06
It should be 00:06.

This wreaks havoc on every date parser I can think to use and every format string I can come up with.

This problem may exist elsewhere in date outputs, but I'm currently running into this one.

[gdevenyi]

Oh my why isn't this in ISO format...

[darkpixel]

Well...there is that...but I'll take whatever reasonable date format I can get. :)

[misterbigstuff]

zfs get -p

[darkpixel]

I completely missed the -p arg in the docs. Thanks!

Should this be closed since the -p option is available? While the default output format is ugly I'm not entirely sure if it's a bug or not.

[gdevenyi]

I would say both the original question and -p need to be better documented.

I can't tell what format "creation" is supposed to be in (and if its configurable somewhere), and I also can't tell what units it is if -p is specified (although I can guess)

[behlendorf]

I'd like to see the missing zero padding added if anyone wants to tackle this. I agree it's jarring to read. And documentation improvements for -p would be welcome.