From: Kent Gibson <warthog618@gmail.com>
To: "Hollerer Franz, Schrack Seconet AG,
Entwicklung" <f.hollerer@schrack-seconet.com>
Cc: "linux-gpio@vger.kernel.org" <linux-gpio@vger.kernel.org>,
"Ullrich Lucas, Schrack Seconet AG,
Entwicklung" <l.ullrich@schrack-seconet.com>,
Bartosz Golaszewski <brgl@bgdev.pl>
Subject: Re: [libgpiod]: non-exclusive use of input lines
Date: Thu, 13 Jul 2023 19:08:41 +0800 [thread overview]
Message-ID: <ZK/bOWcl0x/1zIY2@sol> (raw)
In-Reply-To: <1337f994e3ad45f49dc86787bcb3a019@schrack-seconet.com>
On Thu, Jul 13, 2023 at 09:24:03AM +0000, Hollerer Franz, Schrack Seconet AG, Entwicklung wrote:
>
> I have several processes (one of them is a shell scripts, others are
> C/C++ programs) which need to read the same input line.
> Is it somehow possible to request input lines for non-exclusive use?
No, it is not possible.
> If not, is this a feature which will be added sometime in the future?
>
No, there are no plans for such a feature, AFAIAA.
The solution is to have a userspace process monitor the line and share
the value with the other processes. How best to do that is up to you.
A simple approach would be to write the value to a file.
(which might be a useful mode to add to gpiomon??)
Bart is working on a daemon that may provided shared read access, but
I'm just guessing.
Cheers,
Kent.
prev parent reply other threads:[~2023-07-13 11:08 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-13 9:24 [libgpiod]: non-exclusive use of input lines Hollerer Franz, Schrack Seconet AG, Entwicklung
2023-07-13 11:08 ` Kent Gibson [this message]
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