unix - script to extract the details from xml

Question

if have any xml file as below:

<soap env="abc" id="xyz">
<emp>acdf</emp>
<Workinstance name="ab" id="ab1">
<x>1</x>
<y>2</y>
</Workinstance>
<projectinstance name="cd" id="cd1">
<u>1</u>
<v>2</v>
</projectinstance>
</soap>

I want to extract the id field in workinstance using unix script

I tried grep but, it is retrieving the whole xml file. Can someone help me how to get it?

Answer 1

You might want to consider something like XMLStarlet, which implements the XPath/XQuery specifications.

Parsing XML with regular expressions is essentially impossible even under the best of conditions, so the sooner you give up on trying to do this with grep, the better off you're likely to be.