Which stage-package is `od` command part of?


On ubuntu 16.04: od is part of coreutils.
$ dpkg -S /usr/bin/od
coreutils: /usr/bin/od
When I include stage-packages: [coreutils] as a stage package the bin folder doesn’t include od binary.

I am using od command in my application can you please help on how to include it?


The binary od is already a part of the core snap so you don’t need to ship it in your snap. The package coreutils is correct, you can verify that by running dpkg -S coreutils. Whatever is causing your program not to find it is another problem.


Thanks for responding @zyga. The error thrown by apparmor when using od is /usr/bin/od permission denied. I am running snap on ubuntu16.04, why is it trying to use host os binaries? Shouldn’t it use binaries from snap/core/bin? Also the snap core bin directory also doesn’t contain od binary.

Apologies if some of my interpretation is wrong I am new to snaps.


Looks like /usr/bin/od is missing from the default apparmor template. Since od seems relatively harmless, perhaps @jdstrand could add it to the default apparmor template as part of the updates for 2.39 or 2.40?


It is. In the snap runtime the core snap’s directory hierarchy is mapped as the root file system, however there’s a white list in snapd on which binaries are accessible.


@ijohnson yeah, seems like something we should add for 2.39


@zyga meanwhile can you please guide if is there any way to use od binary in my application? As I mentioned earlier I tried including stage-packages: [coreutils] in my yaml but didn’t work.


Added a quick PR to allow snaps to run /usr/bin/od https://github.com/snapcore/snapd/pull/6768


@prasha stage-packages: [coreutils] should leave od in usr/bin/. I notice you say

did you check usr/bin?


@chipaca yes snaps bin dir doesn’t contain od binary even after using core-utils in stage-packages


did you check usr/bin? Not bin/; usr/bin/.
If I put stage-packages: [coreutils], I get usr/bin/od in the snap. Why wouldn’t you get the same? Please check that directory.


Just for everyone’s sake:

name: od
base: core18
version: current
summary: od in a snap
description: |
  A PoC for https://forum.snapcraft.io/t/which-stage-package-is-od-command-part-of/11067

grade: stable
confinement: strict

    plugin: nil
    - coreutils
    - usr/bin/od

    command: od

root@snapcraft-od:~# tree stage
└── usr
    └── bin
        └── od
$ snap run od --version
od (GNU coreutils) 8.28
Copyright (C) 2017 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Jim Meyering.