[PHP] Re: Recursive Threading with PHP and MySQL.
recursion is something that can be fun and practical at times, other times
its a bad coder trying to do something they think is clever. use it wisly.
?php
function power($num, $power = 1)
{
if ($num != 2)
$power = power(($num/2), $power+1);
return $power;
}
echo power(16);
?
this example is purposely coded bad to show you how recursion can mess up
with bad error checking. this example will work. change to power(30) and
you'll get a segfault because $num will allways equal anything but 2. this
gives you a starting point on recursion.
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Chris Lee
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Alawi [EMAIL PROTECTED] wrote in message
002201c17dc2$75276cd0$753f47d4@mcsh2l7jqy8bgj">news:002201c17dc2$75276cd0$753f47d4@mcsh2l7jqy8bgj...
I want to know how can i do that Recursive loop to get categories as example
can any body help me by give my tutorial or any thing to understand this
techniqe
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Re: [PHP] Re: Recursive Threading with PHP and MySQL.
Recursive functions are generally a bad idea especially in php. By using a recursive function it is possible you may smash the stack, which will crash an apache child (segfaults) and on a multi-threaded server take down the whole webserver. Even with a default memory limit of 8 megs an attacker could crash php by accessing the same thread multiple times. This is NOT a theoretical situation, I've actually came across it while writing a tree drawing code for a forum. The problem exists in all the php that I've tested (PHP 4.0.5,4.0.6,4.1.0RC5). -- PHP General Mailing List (http://www.php.net/) To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] To contact the list administrators, e-mail: [EMAIL PROTECTED]
