mcookie(1) - phpMan

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 output of the MD5 message digest fed with
various pieces of random information: the current time, the process id, the parent process
id, and optionally the contents of an input file. and several bytes of information from
the first of the following devices which is present: /dev/random, /dev/urandom, files in
/proc, /dev/audio.

OPTIONS
-f, --file=FILE
Use file as a macig cookie seed. When file is defined as `-' character input is
read from stdin.

-v, --verbose
Explain what is being done.

-V, --version
Output version information and exit.

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

BUGS
The entropy in the generated 128-bit is probably quite small (and, therefore, vulnerable
to attack) unless a non-pseudorandom number generator is used (e.g., /dev/random under
Linux).

It is assumed that none of the devices opened will block.

FILES
/dev/random
/dev/urandom
/dev/audio
/proc/stat
/proc/loadavg