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udevadm(8) [linux man page]

UDEVADM(8)							      udevadm								UDEVADM(8)

NAME
udevadm - udev management tool SYNOPSIS
udevadm [--debug] [--version] [--help] udevadm info options udevadm trigger [options] udevadm settle [options] udevadm control command udevadm monitor [options] udevadm test [options] devpath DESCRIPTION
udevadm expects a command and command specific options. It controls the runtime behavior of udev, requests kernel events, manages the event queue, and provides simple debugging mechanisms. OPTIONS
--debug Print debug messages to stderr. --version Print version number. --help Print help text. udevadm info options Queries the udev database for device information stored in the udev database. It can also query the properties of a device from its sysfs representation to help creating udev rules that match this device. --query=type Query the database for specified type of device data. It needs the --path or --name to identify the specified device. Valid queries are: name, symlink, path, property, all. --path=devpath The devpath of the device to query. --name=file The name of the device node or a symlink to query --root The udev root directory: /dev. If used in conjunction with a name or symlink query, the query returns the absolute path including the root directory. --run The udev runtime directory: /run/udev. --attribute-walk Print all sysfs properties of the specified device that can be used in udev rules to match the specified device. It prints all devices along the chain, up to the root of sysfs that can be used in udev rules. --export Print output as key/value pairs. Values are enclosed in single quotes. --export-prefix=name Add a prefix to the key name of exported values. --device-id-of-file=file Print major/minor numbers of the underlying device, where the file lives on. --export-db Export the content of the udev database. --cleanup-db Cleanup the udev database. --version Print version. --help Print help text. udevadm trigger [options] Request device events from the kernel. Primarily used to replay events at system coldplug time. --verbose Print the list of devices which will be triggered. --dry-run Do not actually trigger the event. --type=type Trigger a specific type of devices. Valid types are: devices, subsystems. The default value is devices. --action=action Type of event to be triggered. The default value is change. --subsystem-match=subsystem Trigger events for devices which belong to a matching subsystem. This option can be specified multiple times and supports shell style pattern matching. --subsystem-nomatch=subsystem Do not trigger events for devices which belong to a matching subsystem. This option can be specified multiple times and supports shell style pattern matching. --attr-match=attribute=value Trigger events for devices with a matching sysfs attribute. If a value is specified along with the attribute name, the content of the attribute is matched against the given value using shell style pattern matching. If no value is specified, the existence of the sysfs attribute is checked. This option can be specified multiple times. --attr-nomatch=attribute=value Do not trigger events for devices with a matching sysfs attribute. If a value is specified along with the attribute name, the content of the attribute is matched against the given value using shell style pattern matching. If no value is specified, the existence of the sysfs attribute is checked. This option can be specified multiple times. --property-match=property=value Trigger events for devices with a matching property value. This option can be specified multiple times and supports shell style pattern matching. --tag-match=property Trigger events for devices with a matching tag. This option can be specified multiple times. --sysname-match=name Trigger events for devices with a matching sys device name. This option can be specified multiple times and supports shell style pattern matching. --parent-match=syspath Trigger events for all children of a given device. udevadm settle [options] Watches the udev event queue, and exits if all current events are handled. --timeout=seconds Maximum number of seconds to wait for the event queue to become empty. The default value is 120 seconds. A value of 0 will check if the queue is empty and always return immediately. --seq-start=seqnum Wait only for events after the given sequence number. --seq-end=seqnum Wait only for events before the given sequence number. --exit-if-exists=file Stop waiting if file exists. --quiet Do not print any output, like the remaining queue entries when reaching the timeout. --help Print help text. udevadm control command Modify the internal state of the running udev daemon. --exit Signal and wait for udevd to exit. --log-priority=value Set the internal log level of udevd. Valid values are the numerical syslog priorities or their textual representations: err, info and debug. --stop-exec-queue Signal udevd to stop executing new events. Incoming events will be queued. --start-exec-queue Signal udevd to enable the execution of events. --reload-rules Signal udevd to reload the rules files. The udev daemon detects changes automatically, this option is usually not needed. Reloading rules does not apply any changes to already existing devices. --property=KEY=value Set a global property for all events. --children-max=value Set the maximum number of events, udevd will handle at the same time. --timeout=seconds The maximum number seonds to wait for a reply from udevd. --help Print help text. udevadm monitor [options] Listens to the kernel uevents and events sent out by a udev rule and prints the devpath of the event to the console. It can be used to analyze the event timing, by comparing the timestamps of the kernel uevent and the udev event. --kernel Print the kernel uevents. --udev Print the udev event after the rule processing. --property Also print the properties of the event. --subsystem-match=string[/string] Filter events by subsystem[/devtype]. Only udev events with a matching subsystem value will pass. --tag-match=string Filter events by property. Only udev events with a given tag attached will pass. --help Print help text. udevadm test [options] devpath Simulate a udev event run for the given device, and print debug output. --action=string The action string. --subsystem=string The subsystem string. --help Print help text. AUTHOR
Written by Kay Sievers kay.sievers@vrfy.org. SEE ALSO
udev(7) udevd(8) udev 07/30/2011 UDEVADM(8)
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