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Bug #2674 unset() does noet work inside function
Submitted: 1999-11-05 19:20 UTC Modified: 1999-11-22 21:40 UTC
From: gert at wins dot uva dot nl Assigned:
Status: Closed Package: Scripting Engine problem
PHP Version: 4.0 Beta 2 OS: Solaris 7 (x86 and SPARC) and So
Private report: No CVE-ID: None
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 [1999-11-05 19:20 UTC] gert at wins dot uva dot nl 
<?php

function bla()
{
    global      $xxxx;
    unset($xxxx);
}

$xxxx = 1;
echo "xxxx = $xxxx<br>";
unset($xxxx);
echo "xxxx = $xxxx<br>";
$xxxx = 1;
bla();
echo "xxxx = $xxxx<br>";

exit();
?>

I would expect unset() to obliterate a variable in both cases above.
For some reason unset() doesn't  do that when requested to unset
a variable declared global inside a function.

My config reads:

./configure \
        --with-mysql=/opt/mysql \
        --with-apache=../apache_1.3.9 \
        --with-config-file-path=/home/www/WWW/httpd/conf \
        --enable-track-vars \
        --enable-thread-safety \
        --with-system-regex

I don't think its relevant, but my mysql is version mysql-3.22.22.

The enable-thread-safety is not relevant (error shows with and without).

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 [1999-11-22 21:40 UTC] zeev at cvs dot php dot net 
This is a known incompatibility with PHP 3.0, that is consistent with the way PHP 4.0 works.

In PHP 4.0, when you write 'global $foo;' you basically hint PHP
to create a reference to the global variable $foo, with the local name $foo.

When you later on call unset($foo), PHP disallocates the local reference,
and not the global variable that reference points to.

You can unset global variables by using the special $GLOBALS array:
unset($GLOBALS["foo"]);
should work.
 
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