Question

In a shell script (Linux, bash, #!/bin/sh) I have a variable containing XML data like this:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<interface>
    <objects retrieved="0" total="0"/>
</interface>

Some error handling is already done when getting this data, so focus on the actual question please.
And the question is: easy/effective way of reading the “objects” element’s attribute data (named “retrieved”). It can be 0 or 1. (and nothing else).
I guess I have two options: regular expressions and XML-parsing with some external program. But which one should I choose?
Thanks in advance.

Answer 1

You can use xmlstarlet to get the attr:

$ xmlstarlet sel -t -m //objects -v @retrieved input.xml
0

Or

$ xmlstarlet sel -t -m //objects/@retrieved -v . input.xml

---

-m or --match <xpath>     - match XPATH expression
-v or --value-of <xpath>  - print value of XPATH expression