ID: 46097
User updated by: RQuadling at GMail dot com
Reported By: RQuadling at GMail dot com
-Status: Feedback
+Status: Open
Bug Type: Math related
Operating System: Windows XP SP3
PHP Version: 5.3.0alpha2
New Comment:
Other than "Note: As of PHP 4.2.0, there is no need to seed the
random number generator with srand() or mt_srand() as this is now
done automatically."
No difference if the srand() is OUTSIDE of the loop.
Inside the loop, then I get my random data correctly.
<?php
$i_Count = 0; // By the 6'th loop, we are stuck on 32767.
while(++$i_Count <= 20) {
srand();
$s_Data = '';
$j = rand();
for($i = 0 ; $i < $j ; ++$i) {
$s_Data .= chr(rand(0, 255));
}
echo $i_Count, ' ', $j, ' ', strlen($s_Data), "\n";
}
Previous Comments:
------------------------------------------------------------------------
[2008-10-26 19:08:44] [EMAIL PROTECTED]
What if you actually seed it first? See http://php.net/srand
------------------------------------------------------------------------
[2008-09-16 16:39:55] RQuadling at GMail dot com
Description:
------------
Hi.
I was testing an encryption/decryption routine by passing it random
lengths of random data.
I realized that in a very short amount of time, all the strings being
tested were the same length.
I've reduced the string building code to the bare minimum.
Reproduce code:
---------------
<?php
$i_Count = 0; // By the 6'th loop, we are stuck on 32767.
while(++$i_Count <= 20) {
$s_Data = '';
$j = rand();
for($i = 0 ; $i < $j ; ++$i) {
$s_Data .= chr(rand(0, 255));
}
echo $i_Count, ' ', $j, ' ', strlen($s_Data), "\n";
}
Expected result:
----------------
1 randomvalue1 randomvalue1
2 randomvalue2 randomvalue2
3 randomvalue3 randomvalue3
4 randomvalue4 randomvalue4
5 randomvalue5 randomvalue5
6 randomvalue6 randomvalue6
7 randomvalue7 randomvalue7
8 randomvalue8 randomvalue8
9 randomvalue9 randomvalue9
10 randomvalue10 randomvalue10
11 randomvalue11 randomvalue11
12 randomvalue12 randomvalue12
13 randomvalue13 randomvalue13
14 randomvalue14 randomvalue14
15 randomvalue15 randomvalue15
16 randomvalue16 randomvalue16
17 randomvalue17 randomvalue17
18 randomvalue18 randomvalue18
19 randomvalue19 randomvalue19
20 randomvalue20 randomvalue20
Actual result:
--------------
1 randomvalue1 randomvalue1
2 randomvalue2 randomvalue2
3 randomvalue3 randomvalue3
4 randomvalue4 randomvalue4
5 randomvalue5 randomvalue5
6 32767 32767
7 32767 32767
8 32767 32767
9 32767 32767
10 32767 32767
11 32767 32767
12 32767 32767
13 32767 32767
14 32767 32767
15 32767 32767
16 32767 32767
17 32767 32767
18 32767 32767
19 32767 32767
20 32767 32767
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/?id=46097&edit=1
