Get root node

/*

Get textNode content

/obj/textNode()

Get CDATA content

/obj/substringData()

Select items not having 'attribute'

//obj[not(@attribute)]

Select items not having 'child'

//obj[not(./child)]

Select an attribute

//obj/@attrName

Find all nodes where name attribute length is longer than 12

//*[string-length(@name) > 12]

Make Xpath search in linux shell

xmllint --xpath '//nodes' target.xml