User Commands dbus-uuidgen(1)
NAME
dbus-uuidgen - Utility to generate UIDs
SYNOPSIS
dbus-uuidgen [--ensure=file] [--get=file] [--version]
DESCRIPTION
The dbus-uuidgen command generates or reads a universally
unique ID.
Note that the D-Bus UID has no relationship to RFC 4122 and
does not generate UIDs compatible with that spec. Many
systems have a separate command for that (often called
"uuidgen").
The primary usage of dbus-uuidgen is to run in the post-
install script of a D-Bus package as shown in the example
section of this document.
This will ensure that /var/lib/dbus/machine-id exists and
has the uuid in it. It will not overwrite an existing uuid,
since this id should remain fixed for a single machine until
the next reboot at least.
The important properties of the machine UID are that 1) it
remains unchanged until the next reboot and 2) it is dif-
ferent for any two running instances of the OS kernel. That
is, if two processes see the same UID, they should also see
the same shared memory, UNIX domain sockets, local X
displays, localhost.localdomain resolution, process IDs, and
so forth.
If you run dbus-uuidgen with no options it just prints a new
uuid made up out of thin air.
If you run dbus-uuidgen with --get, it prints the machine
UID by default, or the UID in the specified file if you
specify a file.
If you try to change an existing machine-id on a running
system, it will probably result in bad things happening. Do
not try to change this file. Also, do not make it the same
on two different systems; it needs to be different anytime
there are two different kernels running.
The UID should be different on two different virtual
machines, because there are two different kernels.
See http:/www.freedesktop.org/software/dbus/ for more
information.
SunOS 5.11 Last change: 19 Nov 2007 1
User Commands dbus-uuidgen(1)
OPTIONS
The following options are supported:
--ensure=file
If a file is not given, defaults to
/var/lib/dbus/machine-id. If this file exists then it
will be validated, and a failure code returned if it
contains the wrong thing. If the file does not exist,
it will be created with a new uuid in it. On success,
prints no output.
--get=file
If a file is not given, defaults to
/var/lib/dbus/machine-id. If this file exists and is
valid, the uuid in the file is printed on stdout. Other-
wise, the command exits with a nonzero status.
--version
Print the version of dbus-uuidgen
EXAMPLES
Example 1: The primary usage of dbus-uuidgen is to run in
the post-install script of a D-Bus package
dbus-uuidgen --ensure
EXIT STATUS
The following exit values are returned:
0 Application exited successfully
>0 Application exited with failure
FILES
The following files are used by this application:
/usr/bin/dbus-uuidgen Executable for dbus-uuidgen
SunOS 5.11 Last change: 19 Nov 2007 2
User Commands dbus-uuidgen(1)
/var/lib/dbus/machine-id File containing the uuid
generated for this machine.
ATRIBUTES
See attributes(5) for descriptions of the following attri-
butes:
ATRIBUTE TYPE ATRIBUTE VALUE
Availability SUNWdbus
Interface stability Volatile
SEE ALSO
dbus-cleanup-sockets(1), dbus-daemon(1), dbus-launch(1),
dbus-monitor(1), dbus-send(1), libdbus-glib-1(3), attri-
butes(5)
NOTES
For authorship information refer to
http:/www.freedesktop.org/software/dbus/doc/AUTHORS.
Updated by Brian Cameron, Sun Microsystems Inc., 2007.
Please send bug reports to the D-Bus mailing list or bug
tracker, see http:/www.freedesktop.org/software/dbus/
SunOS 5.11 Last change: 19 Nov 2007 3
|