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.
--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.