NAME

       uuidd - UUID generation daemon

SYNOPSIS

       uuidd [options]

DESCRIPTION

       The uuidd daemon is used by the UUID library to generate universally unique identifiers
       (UUIDs), especially time-based UUIDs, in a secure and guaranteed-unique fashion, even in
       the face of large numbers of threads running on different CPUs trying to grab UUIDs.

OPTIONS

       -C, --cont-clock opt_arg
           Activate continuous clock handling for time based UUIDs. uuidd could use all possible
           clock values, beginning with the daemon’s start time. The optional argument can be
           used to set a value for the max_clock_offset. This gurantees, that a clock value of a
           UUID will always be within the range of the max_clock_offset. '-C' or '--cont-clock'
           enables the feature with a default max_clock_offset of 2 hours. '-C<NUM>[hd]' or
           '--cont-clock=<NUM>[hd]' enables the feature with a max_clock_offset of NUM seconds.
           In case of an appended h or d, the NUM value is read in hours or days. The minimum
           value is 60 seconds, the maximum value is 365 days.

       -d, --debug
           Run uuidd in debugging mode. This prevents uuidd from running as a daemon.

       -F, --no-fork
           Do not daemonize using a double-fork.

       -k, --kill
           If currently a uuidd daemon is running, kill it.

       -n, --uuids number
           When issuing a test request to a running uuidd, request a bulk response of number
           UUIDs.

       -P, --no-pid
           Do not create a pid file.

       -p, --pid path
           Specify the pathname where the pid file should be written. By default, the pid file is
           written to {runstatedir}/uuidd/uuidd.pid.

       -q, --quiet
           Suppress some failure messages.

       -r, --random
           Test uuidd by trying to connect to a running uuidd daemon and request it to return a
           random-based UUID.

       -S, --socket-activation
           Do not create a socket but instead expect it to be provided by the calling process.
           This implies --no-fork and --no-pid. This option is intended to be used only with
           systemd(1). It needs to be enabled with a configure option.

       -s, --socket path
           Make uuidd use this pathname for the unix-domain socket. By default, the pathname used
           is {runstatedir}/uuidd/request. This option is primarily for debugging purposes, since
           the pathname is hard-coded in the libuuid library.

       -T, --timeout number
           Make uuidd exit after number seconds of inactivity.

       -t, --time
           Test uuidd by trying to connect to a running uuidd daemon and request it to return a
           time-based UUID.

       -h, --help
           Display help text and exit.

       -V, --version
           Print version and exit.

EXAMPLE

       Start up a daemon, print 42 random keys, and then stop the daemon:

           uuidd -p /tmp/uuidd.pid -s /tmp/uuidd.socket
           uuidd -d -r -n 42 -s /tmp/uuidd.socket
           uuidd -d -k -s /tmp/uuidd.socket

AUTHOR

       The uuidd daemon was written by Theodore Ts’o <tytso@mit.edu>.

SEE ALSO

       uuid(3), uuidgen(1)

REPORTING BUGS

       For bug reports, use the issue tracker at https://github.com/util-linux/util-linux/issues.

AVAILABILITY

       The uuidd command is part of the util-linux package which can be downloaded from Linux
       Kernel Archive <https://www.kernel.org/pub/linux/utils/util-linux/>.