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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Hotplug events do not fire when application is running inside of a docker container","articleBody":"**Environment:**\r\n - OS: Debian Bullseye\r\n - Java version Temurin JDK 21  (repeatable in Amazon Corretto 17 and 11 as well)\r\n - usb4java version 1.3.0\r\n\r\n**Bug description**\r\nWhen running an application on Linux on the host, you can run a java application and have the attach and detach events fire.  When running the same application in a Docker container, those events will not fire.  Further, trying to manually poll the USB devices and compare old/new is not possible, as the devices returned from `UsbHostManager.getUsbServices().getRootUsbHub()` are always the same.  Ex. When a device is no longer attached, it will still appear in the list if it was attached at startup.\r\n\r\n**Reproduction**\r\n1. Compile the code below into a jar file.\r\n```\r\nimport javax.usb.UsbException;\r\nimport javax.usb.UsbHostManager;\r\nimport javax.usb.event.UsbServicesEvent;\r\nimport javax.usb.event.UsbServicesListener;\r\n\r\npublic class Application {\r\n\r\n    public static void main(String[] args) throws UsbException, InterruptedException {\r\n        UsbHostManager.getUsbServices().addUsbServicesListener(new UsbServicesListener() {\r\n            @Override\r\n            public void usbDeviceAttached(UsbServicesEvent event) {\r\n                System.out.println(\"Device attached.\");\r\n            }\r\n\r\n            @Override\r\n            public void usbDeviceDetached(UsbServicesEvent event) {\r\n                System.out.println(\"Device detached.\");\r\n            }\r\n        });\r\n\r\n        Thread.sleep(15000);\r\n    }\r\n}\r\n\r\n```\r\n3. Run on a linux machine with sudo.  `sudo java -Djava.security.egd=file:/dev/./urandom -jar app.jar`\r\n4. Connect and disconnect USB devices to see console output.\r\n5. Build the jar into a container and use the below Dockerfile to build with `sudo docker build --build-arg=\"JAR_FILE=app.jar\" -t test1 .`\r\n```\r\nFROM eclipse-temurin:21-jre-jammy\r\nARG JAR_FILE\r\nCOPY ${JAR_FILE} /usr/app/app.jar\r\nENTRYPOINT [\"java\",\"-Djava.security.egd=file:/dev/./urandom\",\"-jar\",\"/usr/app/app.jar\"]\r\n```\r\n6. Run the container with `sudo docker run -it --rm --privileged test1:latest`\r\n7. Observe that connecting and disconnecting does not fire the event.\r\n\r\n**Expected behavior**\r\nI expect that the application running in a container with the correct privileges' would allow firing of the attach and detach events.\r\n","author":{"url":"https://github.com/westinpigott","@type":"Person","name":"westinpigott"},"datePublished":"2023-12-07T20:30:56.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/90/usb4java/issues/90"}