A terminal shows the nsysctl command and its output in XML: % nsysctl --libxo=pretty,xml -D kern.ostype <object> <OID>1.1</OID> <name>kern.ostype</name> <label></label> <description>Operating system type</description> <type>string</type> <format>A</format> <flags> <flag>RD</flag> <flag>MPSAFE</flag> <flag>CAPRD</flag> </flags> <handler>Defined</handler> <value>FreeBSD</value> </object>