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Date: Thu, 07 Jun 2012 21:44:21 +0200
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Subject: Re: [PHP-DEV] concatenation operator
From: johannes@schlueters.de (Johannes =?ISO-8859-1?Q?Schl=FCter?=)

On Thu, 2012-06-07 at 11:50 -0700, Adi Mutu wrote:
> 
> that's nice, but i haven't understood a thing...i know something about
> php core and php extensions, but nothing about the Zend engine
> specific. 

The mentioned place is directly in the VM, which in general is harder to
understand, but well, it directs to the "concat_function" on
http://lxr.php.net/xref/PHP_TRUNK/Zend/zend_operators.c#1234

Knowing basic C should be enough to understand the code there. The
actual "algorithm" can also easily be guessed (allocate a buffer which
can hold both strings at once and copy them over,the code is a tiny bit
more complex as it tries tore use an existing buffer than allocating
something completely new)

The question is: What do you actually want to know?

> Can you point me to some resources on this topic?

Unfortunately not. The source is the best documentation we have for
that.

johannes