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MCOOKIE(1)			 User Commands			    MCOOKIE(1)

NAME
       mcookie - generate magic	cookies	for xauth

SYNOPSIS
       mcookie [options]

DESCRIPTION
       mcookie generates a 128-bit random hexadecimal number for use with the
       X authority system. Typical usage:

	  xauth	add :0 . mcookie

       The "random" number generated is	actually the MD5 message digest	of
       random information coming from one of the sources getrandom(2) system
       call, /dev/urandom, /dev/random,	or the libc pseudo-random functions,
       in this preference order. See also the option --file.

OPTIONS
       -f, --file file
	   Use this file as an additional source of randomness (for example
	   /dev/urandom). When file is '-', characters are read	from standard
	   input.

       -m, --max-size number
	   Read	from file only this number of bytes. This option is meant to
	   be used when	reading	additional randomness from a file or device.

	   The number argument may be followed by the multiplicative suffixes
	   KiB=1024, MiB=1024*1024, and	so on for GiB, TiB, PiB, EiB, ZiB and
	   YiB (the "iB" is optional, e.g., "K"	has the	same meaning as	"KiB")
	   or the suffixes KB=1000, MB=1000*1000, and so on for	GB, TB,	PB,
	   EB, ZB and YB.

       -v, --verbose
	   Inform where	randomness originated, with amount of entropy read
	   from	each source.

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

       -V, --version
	   Print version and exit.

FILES
       /dev/urandom

       /dev/random

BUGS
       It is assumed that none of the randomness sources will block.

SEE ALSO
       md5sum(1), X(7),	xauth(1), rand(3)

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

AVAILABILITY
       The mcookie 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/>.

util-linux 2.39.4		  2024-01-31			    MCOOKIE(1)

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<https://man.freebsd.org/cgi/man.cgi?query=mcookie&sektion=1&manpath=FreeBSD+Ports+14.3.quarterly>

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