What does the is_final parameter in xml_parse() do? - php

Question

I'm working on creating a class for xml parsing, and need to use this method from PHP called xml_parse.
It has 3 parameters like so:
int xml_parse ( resource $parser , string $data [, bool $is_final = false ] )
According to the PHP manual is_final it means whether its the last piece of data sent in this parse, but what does this mean? does this something have to do with resource $parser? as far as I'm aware this function does not allow an input stream of data, thus my confusion.
Someone please explain what it does

Answer 1

is_final means that if you are parsing the last line of your $data you must set this parameter to true.
in addition there is a note in the Doc :
Entity errors are reported at the end of the parse. And will only show if the "end" parameter is TRUE
See the sample below from w3schools
<?php
$parser=xml_parser_create();
function char($parser,$data)
{
echo $data;
}
xml_set_character_data_handler($parser,"char");
$fp=fopen("test.xml","r");
while ($data=fread($fp,4096))
{
xml_parse($parser,$data,feof($fp)) or
die (sprintf("XML Error: %s at line %d",
xml_error_string(xml_get_error_code($parser)),
xml_get_current_line_number($parser)));
}
xml_parser_free($parser);
?>