From: Richard <richard_siegfried@systemli.org>
To: kernelnewbies <kernelnewbies@kernelnewbies.org>
Subject: Re: Watching for new files/symlinks/devices in sysfs (possible? which syscall?)
Date: Wed, 14 Jun 2023 00:24:14 +0200 [thread overview]
Message-ID: <75b43ee7-1f29-e5a2-f405-e2acc5c3b794@systemli.org> (raw)
In-Reply-To: <8e4d3659-65da-0eff-0826-8ba86bdfab19@systemli.org>
Update (because someone asked):
udev is no viable alternative.
We tried it with udev, it's too slow. It's about an embedded device
where time is of essence.
And we made some measurements, even simply polling with a python script
in /sys/ is over a second faster than waiting for udev.
-- Richard
On 13.06.23 23:31, Richard wrote:
> Hi,
> is there a possibility, in sysfs, to watch for new symlinks (i.e.
> devices) beeing added to /sys/bus/usb/devices (like with inotify for
> normal directories)?
>
> I know you can use select() (userspace) and sysfs_notify() (kernelspace)
> for attributes , but is there something for folders and new devices (or
> symlinks)?
>
> Thanks,
> -- Richard
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies@kernelnewbies.org
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prev parent reply other threads:[~2023-06-13 22:25 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-13 21:31 Watching for new files/symlinks/devices in sysfs (possible? which syscall?) Richard
2023-06-13 22:24 ` Richard [this message]
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