php-internals

This question already has an answer here: Why can't I access DateTime->date in PHP's DateTime class? Is it a bug? 5 answers Consider the following code sample: $m_oDate = new DateTime('2013-06-12 15:54:25'); print_r($m_oDate); echo $m_oDate->date; Since PHP 5.3, this produces (something like) the following output: DateTime Object ( [date] => 2013-06-12 15:54:25 [timezone_type] => 3 [timezone] => Europe/Amsterdam ) 2013-06-12 15:54:25 However the following code: $m_oDate = new DateTime('2013-06-12 15:54:25'); echo $m_oDate->date; ...simply emits an error: Notice: Undefined property: DateTime::

Hey there. Today I wrote a small benchmark script to compare performance of copying variables vs. creating references to them. I was expecting, that creating references to large arrays for example would be significantly slower than copying the whole array. Here is my benchmark code: <?php $array = array(); for($i=0; $i<100000; $i++) { $array[] = mt_rand(); } function recursiveCopy($array, $count) { if($count === 1000) return; $foo = $array; recursiveCopy($array, $count+1); } function recursiveReference($array, $count) { if($count === 1000) return; $foo = &$array; recursiveReference($array,

Since objects are passed by reference by default now, is there maybe some special case when &$obj would make sense? Objects use a different reference mechanism. &$object is more a reference of a reference. You can't really compare them both. See Objects and references : A PHP reference is an alias, which allows two different variables to write to the same value. As of PHP 5, an object variable doesn't contain the object itself as value anymore. It only contains an object identifier which allows object accessors to find the actual object. When an object is sent by argument, returned or assigned

Edit: Revising My Question When building an external PHP module in C, how do I link shared objects? If your C extension code uses a shared library, you need to declare that in the config.m4 file. I strongly recommend using the ext_skel script that's included in the PHP source to generate a skeleton config.m4: ./ext_skel --extname=myextension Since you're linking to a library, by convention you should use the --with-myextension options (as opposed to --enable-myextension ). Uncomment the relevant lines in the config.m4 and fill in the details of your lib. Something like the following: # --with

Is it possible to see if two array variables point to the same memory location? (they are the same array) Actually, this can be done. Through a php extension. File: config.m4 PHP_ARG_ENABLE(test, whether to enable test Extension support, [ --enable-test Enable test ext support]) if test "$PHP_TEST" = "yes"; then AC_DEFINE(HAVE_TEST, 1, [Enable TEST Extension]) PHP_NEW_EXTENSION(test, test.c, $ext_shared) fi File: php_test.h #ifndef PHP_TEST_H #define PHP_TEST_H 1 #define PHP_TEST_EXT_VERSION "1.0" #define PHP_TEST_EXT_EXTNAME "test" PHP_FUNCTION(getaddress4); PHP_FUNCTION(getaddress); extern

<?php $s = "foobar"; $t = $s; $u = $s; echo PHP_VERSION . "\n"; debug_zval_dump($s); xdebug_debug_zval('s'); Run in PHP 5.6.16 Run in PHP 7.0.2 I think the result (PHP 7) should be: string(6) "foobar" refcount(4) s: (refcount=3, is_ref=0)="foobar" I wonder what makes the difference? Need some explanation. Thanks a lot. ------ update ------ Nikita Popov's - PHP 7 – What changed internally? (P41) http://www.slideshare.net/nikita_ppv/php-7-what-changed-internally In PHP 7 a zval can be reference counted or not. There is a flag in the zval structure which determined this. There are some types