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       dbus-uuidgen - Utility to generate UUIDs


       dbus-uuidgen [--version] [--ensure[=FILENAME]] [--get[=FILENAME]]


       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  separate
       command for that (often called "uuidgen").

       See  for  more  information
       about D-Bus.

       The primary usage of dbus-uuidgen is to run in the post-install  script
       of a D-Bus package like this:
         dbus-uuidgen --ensure

       This  will ensure that /var/lib/dbus/machine-id exists and has the uuid
       in it.  It won't 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
       running  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 it 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. Don't try to change this
       file. Also, don't make it the same on two different systems;  it  needs
       to be different anytime there are two different kernels running.

       The UUID should be different on two different virtual machines, because
       there are two different kernels.


       The following options are supported:

              If    a    filename    is     not     given,     defaults     to
              localstatedir/lib/dbus/machine-id   (localstatedir   is  usually
              /var). If this file exists and is valid, the uuid in the file is
              printed  on  stdout. Otherwise, the command exits with a nonzero

              If    a    filename    is     not     given,     defaults     to
              localstatedir/lib/dbus/machine-id   (localstatedir   is  usually
              /var). 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.

              Print the version of dbus-uuidgen




       Please  send  bug reports to the D-Bus mailing list or bug tracker, see