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Subject: Re: deprecated tools: rfcomm, can we un-deprecate it?
Cc:     Marcel Holtmann <marcel@holtmann.org>
References: <0aad7250-65f9-3e4c-e5ca-434139a9ae64@message-id.googlemail.com>
 <2203E98B-B581-4C14-94DF-164D7E036234@holtmann.org>
To:     BlueZ devel list <linux-bluetooth@vger.kernel.org>
From:   Stefan Seyfried <stefan.seyfried@googlemail.com>
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Date:   Tue, 31 Dec 2019 18:35:37 +0100
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Hi Marcel,

thanks for the response.

Am 26.12.19 um 21:40 schrieb Marcel Holtmann:

>> So is there a way to set up a rfcomm device via bluetoothctl? I could
>> not find one, but maybe I did not look hard enough?
>>
>> If not, could we please un-deprecate rfcomm, because having everyone out
>> there reinvent the functionality in crazy ways probably is not a good idea.
>>
>> Or should I just continue to build the package with --enable-deprecated?
>> But that will ship tools with known unfixed security issues (hcidump).
> 
> have a look at doc/profile-api.txt.

This would be for creating a "rfcomm service" for other devices to
connect to, right? (The equivalent of "rfcomm listen...")

But how would I connect e.g. to my serial module (I got this for trying
it by myself instead of relying on bugreporters results...), so what's
the dbus equivalent of "rfcomm connect hci0 <bdaddr> <channel>"?

Some small example python script for this in test_scripts would be
really useful, as the knowledge on how to handle this seems
non-existent: all the various bluetooth codebases checked (e.g. blueman,
pybluez) just re-implement the code in tools/rfcomm.c's cmd_connect
(socket, bind, connect, ioctl RFCOMMCREATEDEV, ...).

Now from reading the kernel code, RFCOMMCREATEDEV seems to be the way to
create an rfcomm device.
The only place in bluez source code that uses RFCOMMCREATEDEV is...
tools/rfcomm.c.
So maybe the rfcomm tool is not as deprecated as we all thought? ;-)

Best regards,

	Stefan
-- 
Stefan Seyfried

"For a successful technology, reality must take precedence over
 public relations, for nature cannot be fooled." -- Richard Feynman