Udev-166

The Udev package contains programs for dynamic creation of device nodes.

Udev pakett sisaldab programme dünaamiliseks device nodede loomiseks.

Approximate build time: 0.2 SBU Required disk space: 9.3 MB plus 37 MB for testfiles 6.60.1. Installation of Udev

The udev-config tarball contains LFS-specific files used to configure Udev. Unpack it into the Udev source directory:

tar -xvf ../udev-config-20100128.tar.bz2

The udev-testfiles tarball contains files needed to test udev. The file expands to an apparent size of about 37MB but the actual disk usage is less than 7MB.

tar -xvf ../udev-166-testfiles.tar.bz2 --strip-components=1

Create some devices and directories that Udev cannot handle due to them being required very early in the boot process, or by Udev itself:

install -dv /lib/{firmware,udev/devices/{pts,shm}}
mknod -m0666 /lib/udev/devices/null c 1 3

Prepare the package for compilation:

./configure --prefix=/usr \
   --sysconfdir=/etc --sbindir=/sbin \
   --with-rootlibdir=/lib --libexecdir=/lib/udev \
   --disable-extras --disable-introspection

The meaning of the new configure options

• --with-rootlibdir=/lib

This controls where the libudev library is installed. The library needs to be in /lib because it's used by Udev at boot time, before /usr might be available, and the default --rootlibdir is /usr/lib.

• --libexecdir=/lib/udev

This controls where Udev-internal rules and helper programs are installed.

• --disable-extras

This option prevents Udev from installing helper programs and other extras which require more external libraries. These libraries are not part of the base LFS system. See the Udev README file for more information.

• --disable-introspection

This option prevents Udev's instrospection feature, which requires packages not installed as part of the base LFS system. See the Udev README file for more information. Compile the package:

make

Test the package.

make check

Install the package:

make install

Remove an empty documentation directory:

rmdir -v /usr/share/doc/udev

Now install the LFS-specific custom rules files:

cd udev-config-20100128
make install

Install the documentation that explains the LFS-specific rules files:

make install-doc 6.60.2. Contents of Udev

Installed programs: ata_id, cdrom_id, collect, create_floppy_devices, edd_id, firmware.sh, fstab_import, path_id, scsi_id, udevadm, udevd, usb_id, write_cd_rules, and write_net_rules Installed libraries: libudev.{a,so} Installed directories: /etc/udev, /lib/udev, /lib/firmware Short Descriptions

• ata_id Provides Udev with a unique string and additional information (uuid, label) for an ATA drive
• cdrom_id Provides Udev with the capabilities of a CD-ROM or DVD-ROM drive

collect Given an ID for the current uevent and a list of IDs (for all target uevents), registers the current ID and indicates whether all target IDs have been registered create_floppy_devices Creates all possible floppy devices based on the CMOS type edd_id Provides Udev with the EDD ID for a BIOS disk drive firmware.sh Uploads firmware to devices fstab_import Finds an entry in /etc/fstab that matches the current device, and provides its information to Udev path_id Provides the shortest possible unique hardware path to a device scsi_id Provides Udev with a unique SCSI identifier based on the data returned from sending a SCSI INQUIRY command to the specified device udevadm Generic udev administration tool: controls the udevd daemon, provides info from the Udev database, monitors uevents, waits for uevents to finish, tests Udev configuration, and triggers uevents for a given device udevd A daemon that listens for uevents on the netlink socket, creates devices and runs the configured external programs in response to these uevents usb_id Provides Udev with information about USB devices write_cd_rules A script which generates Udev rules to provide stable names for optical drives (see also Section 7.10, “Creating Custom Symlinks to Devices”) write_net_rules A script which generates rules to provide stable names for network interfaces (see also Section 7.13, “Configuring the network Script”) libudev A library interface to udev device information /etc/udev Contains Udev configuration files, device permissions, and rules for device naming