/*++ /* 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()); }