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Date: Sat, 07 Aug 2004 09:14:35 -0400
To: internals@lists.php.net
Subject: Substring writes and buffered char streams
From: jtl_phpdotnet@spamex.com
Message-ID: <php.internals-11988@news.php.net>

Hello PHP gurus,

The php-general list does not believe that PHP allows me to do either of the following:

(1) Writing an arbitrary substring of a string directly to a stream without first creating a string object for the substring.  I.E. There is no print($string, $start, $length) or fwrite($resource, $string, $length, $start).

(2) Creating multiple independent buffered characters streams.  It appears that stdout is the only instance available.

I need to be able to do the first to prevent a costly proliferation of string objects when parsing an input string and producing a new output string from it's substrings.  My experience writing Java parsers for business portals clearly demonstrates that object creation, and particularly string creation, is a limiting factor to throughput.  Fixing this problem in PHP seems easy: we just need to add an optional start-offset parameter to fwrite().

I don't think I absolutely need the second feature, as I'm emulating multiple buffered character streams by saving and restoring the contents of stdout (via the output buffer) when switching between instances.  I just have to keep the application smart about switching so that I can minimize the switch costs.  However, it's possible that this could become an issue.

I can't create or use a PHP module since my customers generally only have FTP access to their web sites -- not even telnet, much less the ability to customize their PHP configuration.

So, is it truly impossible to do these things?  If so, when could I hope to see these features -- or at least feature (1) -- ship with core PHP?

Thank you for your help!
~joe