how can I compare two xml files ?

You may want to check the following links that were posted on the xml-dev
list:

You might find Norm Walsh's diffmk useful:

http://www.sun.com/xml/developers/diffmk/

Jin Zhao wrote:
> 
> Does anybody know any xml diff tool with source available(in any language)
> ? I know there are some java packages from IBM have similar features but
> no source available.
> 
> Thanks,
> 
> Jin

See http://www.deltaxml.com for an xml diff package which is free for 
small files and cheap (99 USD) for larger files. I'm afraid the 
source is not available but there will soon be an embeddable API 
version which can be pipelined with other XML processes, e.g. XSL 
filters.

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Mengel Andre (FV/SLM) *" <Andre.Mengel@xxxxxxxxxxxx> Wrote:
>I want to compare two XML-files in order to
>test if they have 
>the same content. Is it possible to use XSLT >in order to solve this
>(I am not an XSLT-Expert) problem ? What I 
>have in mind is to transform
>both XML-files by using an XSL-sheet. Then 
>after processing I want to
>compare 
>both transformed files byte for byte.


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