Subj : Re: Javascript restriction in Trixie
To   : All
From : Theo
Date : Mon Dec 08 2025 03:05:02

bp@www.zefox.net wrote:
> I just set up another Trixie install for a Pi2Bv1.1, so armv7, for
> use with an Owon vds1022 USB oscilloscope. I have an older install
> (bookworm) on a separate microSD card which works correctly, but the 
> card is too small (8GB) to allow useful working space. The new install
> is less than a year newer than the working one. 
> 
> The new install allows installation of Florentbr's software found at
> GitHub but when the software is run it gets stuck in a loop and can't
> connect to the 'scope:
> 
> bob@raspberrypi:~/OWON-VDS1022-1.1.5-cf19 $ sudo owon-vds-tiny
> env: Linux, Java 25.0.1 arm

That's Java, not Javascript.

> app dir: /opt/owon-vds-tiny
> user dir: /root/.owon-vds-tiny
> locale: en_US, en_US, true
> WARNING: A restricted method in java.lang.System has been called
> WARNING: java.lang.System::load has been called by ch.ntb.usb.LibusbJava in an unnamed module (file:/opt/owon-vds-tiny/lib/ch.ntb.usb-0.5.9.jar)
> WARNING: Use --enable-native-access=ALL-UNNAMED to avoid a warning for callers in this module
> WARNING: Restricted methods will be blocked in a future release unless native access is enabled
> 
> ch.ntb.usb.USBException: LibusbJava.usb_claim_interface: Device or resource busy
>         at com.owon.uppersoft.vds.core.usb.CDevice.open(CDevice.java:91)
>         at com.owon.uppersoft.vds.core.usb.CDevice.getDevices(CDevice.java:300)
>         at com.owon.uppersoft.dso.source.usb.USBSourceManager.refreshUSBPort(USBSourceManager.java:79)
>         at com.owon.uppersoft.dso.source.comm.detect.USBLoopChecker.checkUSBDevice(USBLoopChecker.java:74)
>         at com.owon.uppersoft.dso.source.comm.USBDaemonHelper.onNotConnecting(USBDaemonHelper.java:35)
>         at com.owon.uppersoft.vds.machine.InfiniteDaemonTiny0.onNotConnecting(InfiniteDaemonTiny0.java:37)
>         at com.owon.uppersoft.dso.source.comm.Flow.run(Flow.java:79)
>         at com.owon.uppersoft.dso.global.ControlAppsTiny$1.run(ControlAppsTiny.java:38)
> 
> that never seems to stop.
> 
> The warning prompted me to try running under sudo, but that made no difference.
> 
> On closer inspection, it's not clear the warning has any relevance to the 
> "device or resource busy" message. Busy isn't the same as restricted.
> 
> If anybody's got a suggestion please post!

From various searching it seems this error is to do with something else
already having grabbed the port.  Could be an old run of the app that hasn't
properly stopped, a desktop app (eg GNOME's Nautilus file manager likes to
grab MTP devices, which prevents digiKam downloading photos) or a system
service (eg if appears as a HID device, maybe the system USB keyboard driver
grabs it, or a storage device that got automounted).

Depending on what kind of device it appears as (serial, keyboard, mass
storage, network, ...) see if you can work out what other app might have
grabbed it.  ('sudo lsof' is handy here, if it appears as a device node that
you can grep for)

Theo

--- PyGate Linux v1.5.1
 * Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

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