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Date:   Tue, 18 Apr 2023 13:54:09 +0200
From:   Samuel Thibault <samuel.thibault@ens-lyon.org>
To:     Guillaume Nault <gnault@redhat.com>
Cc:     James Chapman <jchapman@katalix.com>, tparkin@katalix.com,
        edumazet@google.com, davem@davemloft.net, kuba@kernel.org,
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        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] PPPoL2TP: Add more code snippets
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Guillaume Nault, le mar. 18 avril 2023 13:25:38 +0200, a ecrit:
> As I said in my previous reply, a simple L2TP example that goes until PPP
> channel and unit creation is fine. But any more advanced use of the PPP
> API should be documented in the PPP documentation.

When it's really advanced, yes. But here it's just about tunnel
bridging, which is a very common L2TP thing to do.

> I mean, these files document the API of their corresponding modules,
> their scope should be limitted to that (the PPP and L2TP layers are
> really different).

I wouldn't call

+        ret = ioctl(ppp_chan_fd, PPPIOCBRIDGECHAN, &chindx2);
+        close(ppp_chan_fd);
+        if (ret < 0)
+                return -errno;

documentation...

> That shouldn't preclude anyone from describing how to combine L2TP, PPP
> and others to cover more advanced use cases. It's just better done in a
> different file.

A more complete example, yes. I don't plan on taking time to do it.

Samuel