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-rw-r--r--README20
1 files changed, 10 insertions, 10 deletions
diff --git a/README b/README
index 148217d16a..5a8d4cc0b3 100644
--- a/README
+++ b/README
@@ -13,7 +13,7 @@ Tools and rules shipped by udev are not public API and may change at any time.
Never call any private tool in /lib/udev from any external application; it might
just go away in the next release. Access to udev information is only offered
by udevadm and libudev. Tools and rules in /lib/udev and the entire contents of
-the /dev/.udev directory are private to udev and do change whenever needed.
+the /run/udev directory are private to udev and do change whenever needed.
Requirements:
- Version 2.6.34 of the Linux kernel with sysfs, procfs, signalfd, inotify,
@@ -59,21 +59,21 @@ Requirements:
available.
- Some udev extras have external dependencies like:
- libacl, libglib2, libusb, usbutils, pciutils, and gperf.
+ libacl, libglib2, usbutils, pciutils, and gperf.
All these extras can be disabled with configure options.
Setup:
- At bootup, the /dev directory should get the 'devtmpfs' filesystem
mounted. Udev manages the permissions and ownership of the kernel-created
device nodes, and udev possibly creates additional symlinks. If needed, udev also
- works on an empty 'tmpfs' filesystem, but some static device nodes like
- /dev/null, /dev/console, /dev/kmsg are needed to be able to start udev itself.
+ works on an empty 'tmpfs' filesystem, but some device nodes like
+ /dev/null, /dev/console, /dev/kmsg should be created before udevd is started.
- The udev daemon should be started to handle device events sent by the kernel.
- During bootup, the kernel can be asked to send events for all already existing
- devices so that they too can be configured by udev. This is usually done by:
- /sbin/udevadm trigger --type=subsystems
- /sbin/udevadm trigger --type=devices
+ During bootup, the events for already existing devices can be replayed, so
+ that they are configured by udev. This is usually done by:
+ /sbin/udevadm trigger --action=add --type=subsystems
+ /sbin/udevadm trigger --action=add --type=devices
- Restarting the daemon never applies any rules to existing devices.
@@ -82,13 +82,13 @@ Setup:
Operation:
- Based on events the kernel sends out on device creation/removal, udev
- creates/removes device nodes in the /dev directory.
+ creates/removes device nodes and symlinks in the /dev directory.
- All kernel events are matched against a set of specified rules, which
possibly hook into the event processing and load required kernel
modules to set up devices. For all devices, the kernel exports a major/minor
number; if needed, udev creates a device node with the default kernel
- name. If specified, udev applies permissions/ownership to the device
+ device name. If specified, udev applies permissions/ownership to the device
node, creates additional symlinks pointing to the node, and executes
programs to handle the device.