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To: Stanislav Malyshev <stas@zend.com>
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Subject: Re: [PHP-DEV] Re: alternative to the fopen() hack in autoloaders
From: greg@chiaraquartet.net (Greg Beaver)

Stanislav Malyshev wrote:
> Hi!
>
>> A good point.  Fortunately, most streams do store the filename in the
>> stream struct, so this would still probably be possible in the majority
>> of cases.  If not available, the original requested filename is used
>> (the one from the fopen call), so opcode caches probably could just use
>> that.
>
> The problem is, by then the stream will already be opened, i.e. extra
> filesystem call is done.
Hi,

Yes, but let's not forget we're talking about making this:

<?php
if ($fp = @fopen($file, 'r', true)) {
    fclose($fp);
    include $file;
}
// 2 stats, fopen + include
?>

into this:

<?php

if ($fp = @fopen($file, 'r', true)) {
	include($fp);
	fclose($fp);
}
// 1 stat, fopen
?>

Of course 1 stat is worse than no stats.  Perhaps better would be to introduce a function:

if (can_include($file)) {
    include $file;
}

opcode caches could easily snag this, as we could provide a simple hook the way we do with stream_resolve_path().  That would actually make a 0-stat smart autoloader a possibility.  Just in case it isn't obvious, can_include() would be the equivalent to an include_path search followed by is_readable(), which is essentially what the fopen() hack does now.  can_include() would also remove the unnecessary opening of the file that fopen() performs.

Greg