Hey, put this in thedocs somewhere?
regards, Derick On Wed, 9 Jun 2004, Sara Golemon wrote: > That's true. What I left out of my explanation (in order to keep it simple) > is that when you "copy" a variable, a new label is created to point to the > same zval, and the zval's refcount is incrmented but the is_ref flag is > *not* set (I referred to this offhand as non-reference manner of multiple > labels referring to the same value). Then when one of the referring labels > says "I want to change my `copy` of the data." It notices that someone else > is also referring to this value (in a non-reference manner) and "separates" > the zval: This amounts to making a true copy of the zval (with a refcount > of 1, and an is_ref of 0) and decrements the refcount of the original zval > (since one fewer label is referring to it). This is the process known as > "copy on change". > > $foo = 1; > > /* $foo (label) ------> 1(value) (is_ref:0 refcount:1) */ > > $bar = $foo; > > /* $foo (label) -------> 1(value) */ > /* $bar (label) ---/ (is_ref:0 refcount:2) */ > > $foo = 2; > > /* $bar (label) -------> 1(value) (is_ref:0 refcount:1) */ > /* $foo (label) -------> 2(value) (is_ref:0 refcount:1) */ > > -Sara > > Ya just had to make it complicated didn't you. > > -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
