Section: User Commands (1)
Updated: March 2014Index
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mcookie - generate magic cookies for xauth
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 output of the MD5 message
digest fed with random information from one of the sources
libc pseudo-random functions
in this preference order.
- -f, --file=FILE
Use additional file as a macig cookie random seed. When file is defined
as '-' character input is read from stdin.
- -m, --max-size=number
of bytes. This option is meant to be used when reading additional
randomness from a device.
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
- -V, --version
Display version information and exit.
- -h, --help
Display help text and exit.
It is assumed that none of the randomness sources will block.
The mcookie command is part of the util-linux package and is available from
Linux Kernel Archive
- SEE ALSO