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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());
+}