NAME
hal-lock - lock an interface
SYNOPSIS
hal-lock [options]
DESCRIPTION
hal-lock can be used to acquire a lock on a given interface either on a
given device or globally. For more information about both the big
picture and the semantics of HAL locks, refer to the HAL spec which can
be found in /usr/share/doc/hal-doc/spec/hal-spec.html depending on the
distribution.
OPTIONS
The following options are supported:
--interface
The name of the interface to lock.
--run Program to run if the lock was acquired.
--udi The UDI (Unique Device Identifier) of the device object. If this
is ommitted, the global lock will be tried.
--exclusive
Whether the lock can be held by others.
--exit-with-lock
Kill the program if the acquired lock is lost. This only makes
sense if you pass a specific UDI due to the semantics of HAL
locks.
--exit-with-dev
Kill the program if the device is removed. This only makes sense
if you pass a specific UDI due to the semantics of HAL locks.
--help Print out usage.
--version
Print the version.
RETURN VALUE
This program will attempt to grab a lock on a given interface. Unless,
a specific UDI is given, the global lock will be tried. If the lock
was succesfully acquired the program specified by the option --run will
be run and upon termination this program will exit with exit code 0. If
the lock wasn’t acquired or an error occured while taking the lock,
this program will exit with a non-zero exit code and the given program
will not be run.
NOTES
This program is only useful for launching software that doesn’t use HAL
at all (since such software launched using hal-lock would be locked out
itself); for example a partition table editor part-foo may use wrapper
script like this
hal-lock --interface org.freedesktop.Hal.Device.Storage --exclusive
--run /path/to/part-foo-program
BUGS
Please send bug reports to either the distribution or the HAL mailing
list, see http://lists.freedesktop.org/mailman/listinfo/hal on how to
subscribe.
SEE ALSO
hald(8), lshal(1), hal-get-property(1), hal-set-property(1), hal-find-
by-property(1), hal-find-by-capability(1)
AUTHOR
Written by David Zeuthen <david@fubar.dk> with a lot of help from many
others.