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In-Reply-To: <4D3735F3.7020502@garfieldtech.com>
References: <201101190045.31781.larry@garfieldtech.com> <4D368C58.2040903@yahoo.com.au>
 <201101190109.52250.larry@garfieldtech.com> <4D369473.4040608@yahoo.com.au>
 <AANLkTimrHUz7a0kkj8OEB=GZKwt7jiu_ms-T7Xib3V7o@mail.gmail.com>
 <AANLkTim8_aoJYrtRsAOv_5yhJu_jpbQFR3nK9MisNiTU@mail.gmail.com>
 <op.vpkf3ybridpuyk@cataphract-old.dulce.lo.geleia.net> <4D3735F3.7020502@garfieldtech.com>
Date: Wed, 19 Jan 2011 20:14:43 +0100
Message-ID: <AANLkTi=BE4G1cNLDhhimZOzK=6hiMkXdpMMgk7gqAQ14@mail.gmail.com>
To: "larry@garfieldtech.com" <larry@garfieldtech.com>
Cc: internals@lists.php.net
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Subject: Re: [PHP-DEV] How deep is copy on write?
From: peter.e.lind@gmail.com (Peter Lind)

On 19 January 2011 20:05, larry@garfieldtech.com <larry@garfieldtech.com> w=
rote:
> So it sounds like the general answer is that if you pass a complex array =
to
> a function by value and mess with it, data is duplicated for every item y=
ou
> modify and its direct ancestors up to the root variable but not for the r=
est
> of the tree.
>
> For objects, because of their "pass by handle"-type behavior you are
> (usually) modifying the same data directly so there's no duplication.
>
> Does that sound correct?
>
> Related: What is the overhead of a ZVal? =C2=A0I'm assuming it's a fixed =
number
> of bytes.
>

http://lmgtfy.com/?q=3Dphp+zval&l=3D1

Regards
Peter

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