HAL(7) Standards, Environments, and Macros HAL(7)

NAME

hal - overview of hardware abstraction layer

DESCRIPTION

The Hardware Abstraction Layer (HAL) provides a view of the various
hardware attached to a system. This view is updated dynamically as
hardware configuration changes by means of hotplug or other
mechanisms. HAL represents a piece of hardware as a device object. A
device object is identified by a unique identifier and carries a set
of key/value pairs, referred to as device properties. Some properties
are derived from the actual hardware, some are merged from device
information files (.fdi files), and some are related to the actual
device configuration.


HAL provides an easy-to-use API through D-Bus. D-Bus is an IPC
framework that, among other features, provides a system-wide message-
bus that allows applications to talk to one another. Specifically, D-
Bus provides asynchronous notification such that HAL can notify other
peers on the message-bus when devices are added and removed, as well
as when properties on a device are changing.


In the Solaris operating system, HAL is supported by a daemon,
hald(8), and a set of utilities that enable the adding and removing
of devices and the modification of their properties.

SEE ALSO

fdi(5), hald(8)


See the HAL pages, including the HAL specification, under
http://freedesktop.org.

November 26, 2017 HAL(7)