udevadm udevd November 2007 udev udevadm 8 udevadmudev management tool udevadm 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 Print debug messages to stderr. Print version number. Print help text. udevadm info <replaceable>options</replaceable> 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 the database for specified type of device data. It needs the or to identify the specified device. Valid queries are: name, symlink, path, env, all. The devpath of the device to query. The name of the device node or a symlink to query 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. 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. Print major/minor numbers of the underlying device, where the file lives on. Export the content of the udev database. Print version. Print help text. udevadm trigger <optional>options</optional> Request device events from the kernel. Usually used to replay events at system coldplug time. Print the list of devices which will be triggered. Do not actually trigger the event. Trigger a specific type of devices. Valid types are: devices, subsystems, failed. The default value is devices. Type of event to be triggered. The default value is add. Trigger events for devices which belong to a matching subsystem. This option can be specified multiple times and supports shell style pattern matching. 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. 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. 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. udevadm settle <optional>options</optional> Watches the udev event queue, and exits if all current events are handled. Maximum number of seconds to wait for the event queue to become empty. The default value is 180 seconds. A value of 0 will check if the queue is empty and always return immediately. Do not print any output, like the remaining queue entries when reachin the timeout. Print help text. udevadm control <replaceable>command</replaceable> Modify the internal state of the running udev daemon. Set the internal log level of udevd. Valid values are the numerical syslog priorities or their textual representations: , and . Signal udevd to stop executing new events. Incoming events will be queued. Signal udevd to enable the execution of events. Signal udevd to reload the rules from the config. Set global variable. value Set the maximum number of events, udevd will handle at the same time. Print help text. udevadm monitor <optional>options</optional> 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. Print the complete environment for all events. Can be used to compare the kernel supplied and the udev added environment values. Print the kernel uevents. Print the udev event after the rule processing. Print help text. udevadm test <optional>options</optional> <replaceable>devpath</replaceable> Simulate a udev event run for the given device, and print out debug output. Unless forced to, no device node or symlink will be created. The action string. The subsystem string. Force the creation of a device node or symlink. Usually the test run prints only debug output. Print help text. AUTHOR Written by Kay Sievers kay.sievers@vrfy.org. SEE ALSO udev7 udevd8