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Date: Sun, 14 Jan 2024 14:21:34 +0100
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Subject: Re: [PATCH] can: bcm: add recvmsg flags for own, local and remote
 traffic
To: Oliver Hartkopp <socketcan@hartkopp.net>, mkl@pengutronix.de,
 linux-can@vger.kernel.org
Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
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 <14e86ea6-e038-4702-957a-39af27bfc280@hartkopp.net>
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From: Nicolas Maier <nicolas.maier.dev@gmail.com>
In-Reply-To: <14e86ea6-e038-4702-957a-39af27bfc280@hartkopp.net>
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Hello,

Thanks a lot for the feedback!

On 08/01/2024 19:57, Oliver Hartkopp wrote:

> But in the first place I'm interested to know what the use-case for this 
> extension is.

My goal with this extension is to be able to implement a reliable
'CAN send' function in userspace which would check that the message has
been correctly transmitted, or retry if no confirmation was received
after a timeout (I am using a device which empties some TX buffer when
recovering from the Bus-Off state, therefore some messages will be lost,
which is why the reliability needs to be handled elsewhere). For this
purpose, knowing the origin of a received message is needed.

This was already possible with RAW sockets, and the goal here is to
provide the same information when using BCM sockets.

Best regards,
Nicolas