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dbus-uuidgen(1) [opensolaris man page]

dbus-uuidgen(1) 						   User Commands						   dbus-uuidgen(1)

dbus-uuidgen - Utility to generate UUIDs 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 UUID has no relationship to RFC 4122 and does not generate UUIDs compatible with that spec. Many systems have a sepa- rate 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 UUID are that 1) it remains unchanged until the next reboot and 2) it is different for any two run- ning instances of the OS kernel. That is, if two processes see the same UUID, 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 UUID by default, or the UUID 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 run- ning. The UUID should be different on two different virtual machines, because there are two different kernels. See for more information. 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. Otherwise, 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 /var/lib/dbus/machine-id File containing the uuid generated for this machine. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE 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), attributes(5) NOTES
For authorship information refer to Updated by Brian Cameron, Sun Microsystems Inc., 2007. Please send bug reports to the D-Bus mailing list or bug tracker, see SunOS 5.11 19 Nov 2007 dbus-uuidgen(1)

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