X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd.device.xml;h=ac6deafb182e521825f4a8ff9bc396b83f7f93c4;hp=557f15f906d79615e698ad521c1c2274406da719;hb=dd2fd155901a965ec0efa3adc460b33d2048d4c2;hpb=67826132adfdf626413f08fb664debd4a7ec35b7 diff --git a/man/systemd.device.xml b/man/systemd.device.xml index 557f15f90..ac6deafb1 100644 --- a/man/systemd.device.xml +++ b/man/systemd.device.xml @@ -1,7 +1,6 @@ - + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> - - systemd.device - systemd - - - - Developer - Lennart - Poettering - lennart@poettering.net - - - - - - systemd.device - 5 - - - - systemd.device - Device unit configuration - - - - device.device - - - - Description - - A unit configuration file whose name ends in - .device encodes information about - a device unit as exposed in the - sysfs/udev7 - device tree. - - This unit type has no specific options. See - systemd.unit5 - for the common options of all unit configuration - files. The common configuration items are configured - in the generic [Unit] and - [Install] sections. A separate - [Device] section does not exist, - since no device-specific options may be - configured. - - systemd will dynamically create device units for - all kernel devices that are marked with the "systemd" - udev tag (by default all block and network devices, - and a few others). This may be used to define - dependencies between devices and other units. To tag a - udev device, use TAG+="systemd" in - the udev rules file, see - udev7 - for details. - - Device units are named after the - /sys and - /dev paths they control. Example: - the device /dev/sda5 is exposed - in systemd as dev-sda5.device. For - details about the escaping logic used to convert a - file system path to a unit name see - systemd.unit5. - - - - - The udev Database - - The settings of device units may either be - configured via unit files, or directly from the udev - database (which is recommended). The following udev device - properties are understood by systemd: - - - - SYSTEMD_WANTS= - SYSTEMD_USER_WANTS= - Adds dependencies of - type Wants from the - device unit to all listed units. The - first form is used by the system - systemd instance, the second by user - systemd instances. Those settings may - be used to activate arbitrary units - when a specific device becomes - available. - - Note that this and the - other tags are not taken into account - unless the device is tagged with the - systemd string in - the udev database, because otherwise - the device is not exposed as a systemd - unit (see above). - - Note that systemd will only act - on Wants - dependencies when a device first - becomes active. It will not act on - them if they are added to devices that - are already active. Use - SYSTEMD_READY= (see - below) to influence on which udev - event to trigger the dependencies. - - - - - SYSTEMD_ALIAS= - Adds an additional - alias name to the device unit. This - must be an absolute path that is - automatically transformed into a unit - name. (See above.) - - - - SYSTEMD_READY= - If set to 0, systemd - will consider this device unplugged - even if it shows up in the udev - tree. If this property is unset or set - to 1, the device will be considered - plugged if it is visible in the - udev tree. This property has no - influence on the behavior when a - device disappears from the udev - tree. - - This option is useful to support - devices that initially show up in an - uninitialized state in the tree, and - for which a changed - event is generated the moment they are - fully set up. Note that - SYSTEMD_WANTS= (see - above) is not acted on as long as - SYSTEMD_READY=0 is - set for a device. - - - - ID_MODEL_FROM_DATABASE= - ID_MODEL= - - If set, this property is - used as description string for the - device unit. - - - - - - - - - See Also - - systemd1, - systemctl1, - systemd.unit5, - udev7, - systemd.directives7 - - + + systemd.device + systemd + + + + Developer + Lennart + Poettering + lennart@poettering.net + + + + + + systemd.device + 5 + + + + systemd.device + Device unit configuration + + + + device.device + + + + Description + + A unit configuration file whose name ends in + .device encodes information about a device unit + as exposed in the + sysfs/udev7 + device tree. + + This unit type has no specific options. See + systemd.unit5 + for the common options of all unit configuration files. The common + configuration items are configured in the generic + [Unit] and [Install] + sections. A separate [Device] section does not + exist, since no device-specific options may be configured. + + systemd will dynamically create device units for all kernel + devices that are marked with the "systemd" udev tag (by default + all block and network devices, and a few others). This may be used + to define dependencies between devices and other units. To tag a + udev device, use TAG+="systemd" in the udev + rules file, see + udev7 + for details. + + Device units are named after the /sys + and /dev paths they control. Example: the + device /dev/sda5 is exposed in + systemd as dev-sda5.device. For details about + the escaping logic used to convert a file system path to a unit + name see + systemd.unit5. + + + + + The udev Database + + The settings of device units may either be configured via + unit files, or directly from the udev database (which is + recommended). The following udev device properties are understood + by systemd: + + + + SYSTEMD_WANTS= + SYSTEMD_USER_WANTS= + Adds dependencies of type + Wants from the device unit to all listed + units. The first form is used by the system systemd instance, + the second by user systemd instances. Those settings may be + used to activate arbitrary units when a specific device + becomes available. + + Note that this and the other tags are not taken into + account unless the device is tagged with the + systemd string in the udev database, + because otherwise the device is not exposed as a systemd unit + (see above). + + Note that systemd will only act on + Wants dependencies when a device first + becomes active. It will not act on them if they are added to + devices that are already active. Use + SYSTEMD_READY= (see below) to influence on + which udev event to trigger the dependencies. + + + + + SYSTEMD_ALIAS= + Adds an additional alias name to the device + unit. This must be an absolute path that is automatically + transformed into a unit name. (See above.) + + + + SYSTEMD_READY= + If set to 0, systemd will consider this device + unplugged even if it shows up in the udev tree. If this + property is unset or set to 1, the device will be considered + plugged if it is visible in the udev tree. This property has + no influence on the behavior when a device disappears from the + udev tree. + + This option is useful to support devices that initially + show up in an uninitialized state in the tree, and for which a + changed event is generated the moment they + are fully set up. Note that SYSTEMD_WANTS= + (see above) is not acted on as long as + SYSTEMD_READY=0 is set for a + device. + + + + ID_MODEL_FROM_DATABASE= + ID_MODEL= + + If set, this property is used as description + string for the device unit. + + + + + + + + See Also + + systemd1, + systemctl1, + systemd.unit5, + udev7, + systemd.directives7 + +