Select multiple elements with xmlstarlet

Question

Since I could not find an explained example elsewhere, I share my findings as a Q&A.

Consider this list of pupils (pupils.xml):

<pupils>
    <pupil>
        <firstName>Adam</firstName>
        <lastName>Amith</lastName>
        <birthDate>2000-01-01</birthDate>
    </pupil>
    <pupil>
        <firstName>Berta</firstName>
        <lastName>Bmith</lastName>
        <birthDate>2000-01-02</birthDate>
    </pupil>
    <pupil>
        <firstName>Caesar</firstName>
        <lastName>Cmith</lastName>
        <birthDate>2000-01-03</birthDate>
    </pupil>
    <pupil>
        <firstName>Doris</firstName>
        <lastName>Dmith</lastName>
        <birthDate>2000-01-04</birthDate>
    </pupil>
</pupils>

How can I select two subattributes of each pupil to get a list like this:

Adam Amith
Berta Bmith
Caesar Cmith
Doris Dmith

Answer 1

The command to get this is

xmlstarlet select -T -t -m "//pupil" -v "firstName" -o " " -v "lastName" -n pupils.xml

and brings:

Adam Amith
Berta Bmith
Caesar Cmith
Doris Dmith

• -T switches the output to text
• -t -m "//pupil" -v "firstName" -o " " -v "lastName" -n defines a template
  • -m "//pupil" matches every pupil node
  • -v "firstName" prints the value of the firstName subnode (subnode of currently matched node)
  • -o " " prints a blank
  • -v "lastName" (see above)
  • -n prints a newline
• pupils.xml provides the input file

The documentation provides even more advanced parameters.