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/*++
/* NAME
/* myrand 3
/* SUMMARY
/* rand wrapper
/* SYNOPSIS
/* #include <myrand.h>
/*
/* void mysrand(seed)
/* int seed;
/*
/* int myrand()
/* DESCRIPTION
/* This module implements a wrapper for the portable, pseudo-random
/* number generator. The wrapper adds automatic initialization.
/*
/* mysrand() performs initialization. This call may be skipped.
/*
/* myrand() returns a pseudo-random number in the range [0, RAND_MAX].
/* If mysrand() was not called, it is invoked with the process ID
/* ex-or-ed with the time of day in seconds.
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* WARNING
/* Do not use this code for generating unpredictable numbers.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*--*/
/* System library. */
#include <sys_defs.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
/* Utility library. */
#include <myrand.h>
static int myrand_initdone = 0;
/* mysrand - initialize */
void mysrand(int seed)
{
srand(seed);
myrand_initdone = 1;
}
/* myrand - pseudo-random number */
int myrand(void)
{
if (myrand_initdone == 0)
mysrand(getpid() ^ time((time_t *) 0));
return (rand());
}
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