#40724 [Opn->Bgs]: srand returns different results in 5.2.1 than in previous versions

From: Date: Mon, 05 Mar 2007 23:57:53 +0000
Subject: #40724 [Opn->Bgs]: srand returns different results in 5.2.1 than in previous versions
References: 1  Groups: php.bugs 
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ID: 40724 Updated by: iliaa@php.net Reported By: dave at dmorg dot org -Status: Open +Status: Bogus Bug Type: Math related Operating System: linux, windows PHP Version: 5.2.1 New Comment: Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://www.php.net/manual/ and the instructions on how to report a bug at http://bugs.php.net/how-to-report.php Random numbers are random, so you can't expect to get the same number out of a random number generator. Previous Comments: ------------------------------------------------------------------------ [2007-03-05 07:52:38] dave at dmorg dot org Description: ------------ I use srand to seed random numbers with student id numbers so that whenever students relog in to an assignment, their questions have the same input values and they can continue where they left off. I am now getting different results than before. I'm not sure whether this is an unintended consequence of some apparently unrelated code change or whether it is intended. Reproduce code: --------------- <?php mt_srand(42); echo mt_rand(); ?> produces 1387371436 under 4.*, 5.1.1. 5.1.4 produces 1354439493 under 5.2.1 Expected result: ---------------- I would expect results from the random number generator to be consistent when seeded with the same number Actual result: -------------- produces 1387371436 under 4.*, 5.1.1. 5.1.4 produces 1354439493 under 5.2.1 ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=40724&edit=1

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