HPR3394: Be an XML star with xmlstarlet

Hacker Public Radio

English - August 05, 2021 00:00 - 12.4 MB - ★★★★ - 34 ratings
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See the layout of an XML document

$ xmlstarlet elements planets.xml
xml
xml/sol
xml/sol/planet
xml/sol/planet/name
xml/sol/planet/albedo
xml/sol/planet
xml/sol/planet/name
xml/sol/planet/albedo
xml/sol/planet
xml/sol/planet/name
xml/sol/planet/albedo

See content of the planet node

$ xmlstarlet select -t --value-of '/xml/sol/planet' planets.xml

Mercury
0.11

Venus
0.7

Terra
0.39

Get the third instance of the planet node

$ xmlstarlet select -t --value-of '/xml/sol/planet[3]' planets.xml
Terra
0.39

Get only the planets with an albedo greater than 0.25

$ xmlstarlet select -t --value-of '/xml/sol/planet[albedo > 0.25]' planets.xml

Venus
0.7

Terra
0.39

Get only the planets closer to Sol than the third planet

$ xmlstarlet select -t --value-of '/xml/sol/planet[position() < 3]' planets.xml

Mercury
0.11

Venus
0.7

Learn more XPath functions at Mozilla Developer Network.

Download xmlstarlet from xmlstarlet.sourceforge.net.