I want to create a graph using GD in PHP, however, lots of things seem to work different ?? in PHP after the

<?php   
header ('Content-Type: image/gif');

statement I cannot use r_print, it seems that GLOBAL is not working for declaration i functions....

if i then delclare like

$x = 1;

and try to use it as

function err($somevare) {
    GLOBAL $x;

it wont work, and using like

r_print ($someOther);

will also crash picture as not renderable

so my question, there seem to be limitations using GD -- image and rest of PHP, where can I understand this better; would appreciate some help (using PHP 5.2 .... yes I know its old)