splitting an XML file on the basis on basis of XML tags

[bijeshn at gmail.com]

Hi all,

         i have an XML file with the following structure::

<r1>
<r2>-----|
<r3>     |
<r4>     |
.           |
.           |         --------------------> constitutes one record.
.           |
.           |
.           |
</r4>    |
</r3>    |
</r2>----|
<r2>
.
.
.    -----------------------|
.                           |
.                           |
.                           |----------------------> there are n
records in between....
.                           |
.                           |
.                           |
.   ------------------------|
.
.
</r2>
<r2>-----|
<r3>     |
<r4>     |
.           |
.           |         --------------------> constitutes one record.
.           |
.           |
.           |
</r4>    |
</r3>    |
</r2>----|
</r1>


       Here <r1> is the main root tag of the XML, and <r2>...</r2>
constitutes one record. What I would like to do is
to extract everything (xml tags and data) between nth <r2> tag and (n
+k)th <r2> tag. The extracted data is to be
written down to a separate file.

Thanks...