Standards, Environments, and Macros                        hal(5)



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 identifer 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 dev-
     ice 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  dae-
     mon, hald(1M), and a set of utilities that enable the adding
     and removing of devices and the modification of  their  pro-
     perties.

SEE ALSO
     hald(1M), fdi(4)


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



















SunOS 5.11          Last change: 11 Sep 2006                    1