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/* (C) Copyright 2004, 2005, 2006 Stijn van Dongen
*
* This file is part of tingea. You can redistribute and/or modify tingea
* under the terms of the GNU General Public License; either version 2 of the
* License or (at your option) any later version. You should have received a
* copy of the GPL along with tingea, in the file COPYING.
*/
#include <sys/types.h>
#include <unistd.h>
#include <time.h>
#include "rand.h"
unsigned long mcxSeed
( unsigned long i
)
{ pid_t p = getpid()
; pid_t pp = getppid()
; time_t t = time(NULL)
; unsigned long s = (p ^ p << 4 ^ p << 16 ^ p << 28)
^ (pp ^ pp << 8 ^ pp << 24)
^ (t ^ t << 12 ^ t << 20)
^ (i ^ i << 3 ^ i << 23 ^ i << 26)
/* I have no solid evidence backing up the usefulness of the xors.
* They won't increase entropy anyway of course, and this function is
* the worst to use if you want to have a cryptographically strong
* seed. Anyway, the xors do seem useful in order to spread input
* bits out over the output space, as seen from some hashing
* experiments.
*/
; return s
; }
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