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Date: Fri, 11 Nov 2005 09:29:00 -0800
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Subject: Array_merge, safety and race condition?
From: enugroho@spikesource.com (Ezra Nugroho)

I sent this to the general list, but I didn't get definitive answer.
Maybe internals is the better forum to talk about it.
If you have a test code, or other pointers towards a definitive answer,
I'd love to try it.

Thanks




Php experts everywhere,

I want to merge two arrays, and I want to store the result as the first
array. Something like the following:


$array1 = array_merge ($array1, $array2);


So far the code gives me what I want. However, suppose if $array1 is
extremely huge, am I introducing a bug here because of possible race
condition? It's possible that array_merge has two write something to
$array1 (left hand side) before it even finishes reading it (argument)
in the first place. Let alone merging the two.

Should I just go conservative and do:

$tmp = array_merge($array1, $array2);
$array1 = $tmp; 


Thank you,
Ezra