Re: /dev/ttyUSB0 spontaneously changes to /dev/ttyUSB1

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



> as /dev/ttyUSB0.  A wview server attaches to /dev/ttyUSB0 and runs fine
> till suddenly the device disappears from /dev/ttyUSB0 and appears
> as /dev/ttyUSB1, at which time the server fails.  

You need to fix the server.

> I suspect (though without much evidence) that the reason for the device 
> moving around is that there is a brief interruption of service from the
> device, so that it appears to the computer that a *new* device has 
> appeared, which it has to find a device name for before it had deleted
> the old name of the device.

That sounds likely - dmesg will probably tell you.

> Does anyone know of a way to keep the USB device open at a known
> location, maybe by creating a permanent entry in /dev, and bypassing
> udev?  Any more theories about what, in general, is happening?

Even if you overwrote the old device node the server needs to re-open the
file handle. Given the server will get notification that the port has
failed (eg a SIGHUP or going ready for read and getting an error on the
read) it shouldn't be too hard to fix it.

Alan
-- 
users mailing list
users@xxxxxxxxxxxxxxxxxxxxxxx
To unsubscribe or change subscription options:
https://admin.fedoraproject.org/mailman/listinfo/users
Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
Have a question? Ask away: http://ask.fedoraproject.org


[Index of Archives]     [Older Fedora Users]     [Fedora Announce]     [Fedora Package Announce]     [EPEL Announce]     [EPEL Devel]     [Fedora Magazine]     [Fedora Summer Coding]     [Fedora Laptop]     [Fedora Cloud]     [Fedora Advisory Board]     [Fedora Education]     [Fedora Security]     [Fedora Scitech]     [Fedora Robotics]     [Fedora Infrastructure]     [Fedora Websites]     [Anaconda Devel]     [Fedora Devel Java]     [Fedora Desktop]     [Fedora Fonts]     [Fedora Marketing]     [Fedora Management Tools]     [Fedora Mentors]     [Fedora Package Review]     [Fedora R Devel]     [Fedora PHP Devel]     [Kickstart]     [Fedora Music]     [Fedora Packaging]     [Fedora SELinux]     [Fedora Legal]     [Fedora Kernel]     [Fedora OCaml]     [Coolkey]     [Virtualization Tools]     [ET Management Tools]     [Yum Users]     [Yosemite News]     [Gnome Users]     [KDE Users]     [Fedora Art]     [Fedora Docs]     [Fedora Sparc]     [Libvirt Users]     [Fedora ARM]

  Powered by Linux