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Date:   Fri, 22 Jun 2018 16:19:40 -0700
From:   Martin KaFai Lau <kafai@fb.com>
To:     Jakub Kicinski <jakub.kicinski@netronome.com>
CC:     Okash Khawaja <osk@fb.com>, Daniel Borkmann <daniel@iogearbox.net>,
        "Alexei Starovoitov" <ast@kernel.org>, Yonghong Song <yhs@fb.com>,
        Quentin Monnet <quentin.monnet@netronome.com>,
        "David S. Miller" <davem@davemloft.net>, <netdev@vger.kernel.org>,
        <kernel-team@fb.com>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH bpf-next 2/3] bpf: btf: add btf json print functionality
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On Fri, Jun 22, 2018 at 02:49:52PM -0700, Jakub Kicinski wrote:
> On Fri, 22 Jun 2018 14:27:43 -0700, Jakub Kicinski wrote:
> > BTF in JSON is very useful, and will help people who writes simple
> > orchestration/scripts based on bpftool *a* *lot*.  I really appreciate
> > this addition to bpftool and will start using it myself as soon as it
> > lands.  I'm not sure why the reluctance to slightly change the output
> > format?
> 
> Ohh, maybe that's the misunderstanding, you only implemented JSON so
> you wanted it to be as readable and clean as possible.  Hence the hex
> output and cutting out the old cruft!  That perspective makes sense!
> But I think we should keep JSON for machines (but including BTF
> formatted values) and let's make the plain text output nice and clean,
> agreed.
Right, it is what my earlier comment meant on "this ascii output is
for human".  We merely call it json because we are reusing
the json's meaning on {}, [] and int since it fits nicely
on what we want to achieve, readability.  Other than that,
it does not have to follow other json's requirements.
We can call it whatever except json to avoid wrong
user expectation.  Putting it under "-j"/"-p" was a mistake.
Hence, I said this patch belongs to the 'plaintext" output.

If we really needed a similar output under "-j" or "-p", things
had to be changed and it belongs to a separate patch.