mcookie (1) Linux Manual Page
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.
-V, –version
- Display version information and exit.
-h, –help
- Display help text and exit.
Files
/dev/urandom /dev/random