I have a file.xml with <EMAIL>char_data</EMAIL>. Calling the script: http://server/script.php3?file.xml . In function characterData variable $data is empty when it's echoed inside if:

<?php

$filename = $argv[0];
$double = FALSE;

function startElement($parser, $name, $attribs)
{
    global $double;

    echo "<DIV CLASS=\"$name\">\n";

    if ($name == "EMAIL")
        $double = TRUE;
        /* string inside <EMAIL></EMAIL> has to be displayed twice */
}

function endElement($parser, $name)
{
    echo "</DIV>\n";
}

function characterData($parser, $data)
{
    global $double;

    if ($double)
    {
        echo "IF: ","$data"," :ENDIF";
            /* IF: and ENDIF: are displayed but $data is empty */
        $double = FALSE;
    }

    echo "$data"; /* here $data  is ok*/
}

$xml_parser = xml_parser_create();

xml_parser_set_option($xml_parser, XML_OPTION_CASE_FOLDING, true);

xml_set_element_handler($xml_parser, "startElement", "endElement");
xml_set_character_data_handler($xml_parser, "characterData");

if (!($file = fopen($filename, "r")))
    die("could not open XML input");

while ($data = fread($file, 4096))
{
    if (!xml_parse($xml_parser, $data, feof($file)))
    {
        die(sprintf("XML error: %s at line %d",
                    xml_error_string(xml_get_error_code($xml_parser)),
                    xml_get_current_line_number($xml_parser)));
    }
}

xml_parser_free($xml_parser);

?>