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       hald - HAL daemon


       hald [options]


       hald  is a daemon that maintains a database of the devices connected to
       the system system in real-time. The daemon connects to the D-Bus system
       message  bus  to  provide an API that applications can use to discover,
       monitor and invoke operations on devices. For  more  information  about
       both  the  big  picture and specific API details, refer to the HAL spec
       which  can  be   found   in   /usr/share/doc/hal-doc/spec/hal-spec.html
       depending on the distribution.


       The following options are supported:

              Specify whether to run in the foreground or the background.

              Enable verbose debug output.

              Enable  logging of debug output to the syslog instead of stderr.
              Use this option only together with --verbose.

       --help Print out usage.

              Print the version of the daemon and exit.


       Please send bug reports to either the distribution or the  HAL  mailing
       list,  see on how to

       First, to obtain useful debug traces you will need  to  have  debuginfo
       packages  installed.  On  a  Fedora system this is in the hal-debuginfo
       package and can be installed via the yum update program.

       Second, shut down the existing hald daemon instance; on a Fedora system
       this is achieved by

       /etc/init.d/haldaemon stop

       After having shut down the daemon, you might want to run

       pkill hald

       to ensure that all the helper processe of hald are killed too. To start
       the HAL daemon, use

       /usr/sbin/hald --daemon=no --verbose=yes

       If the daemon crashes, you can start it under a debugger via

       gdb /usr/sbin/hald

       and then typing

       run --daemon=no --verbose=yes

       at the (gdb) prompt. To capture a back trace, use the  bt  command  and
       attach this to the bug report.

       Please also attach the output of lshal(1) in the bug report if possible
       (it’s not possible if the hald daemon crashed). If the  nature  of  the
       bug  has  to  do with hotplugging, attach two outputs of lshal(1) - one
       before the device hotplug event and one after.


       udev(7),  dbus-daemon(1),   lshal(1),   hal-set-property(1),   hal-get-
       property(1),  hal-find-by-property(1),  hal-find-by-capability(1), hal-


       Written by David Zeuthen <> with a lot of help from  many