It's a lot clearer now Jenda, thank you for your time and patience.

I was just wondering three things:

1) where does this take the XML data from (a file? -- if so where is it specified?)
2) this line in particular $parser->filter(\*DATA); is it an output or something else?
3) last thing, I get an error when I try to run this perl script (might be because I don't quite understand the input/output of this script) 
Name "main::DATA" used only once: possible typo at sort.pl line 45.
<?xml version="1.0"?>

not well-formed (invalid token) at line 1, column 4, byte 4 
 at sort.pl line 45

[download]
Just off the top of my head, the languages that I'm familiar with: C, C++, Java, Python, XML (seemed relevant in this case :P) and some other things here and there (not counting webdev - doesn't seem relevant here?).

Thank you again for answering my questions. I greatly appreciate it.

In reply to Re^4: Sort xml based on attribute by Anonymous Monk
in thread Sort xml based on attribute by bharathinc

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