--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/relpipe-data/examples/awk-through-xml.sh	Sat Dec 28 16:19:41 2019 +0100
@@ -0,0 +1,62 @@
+#!/bin/bash
+
+getXML() {
+	# Just read a file:
+	cat "/etc/dbus-1/system.d/org.freedesktop.NetworkManager.conf"
+	# Or we can wget or curl it from the network
+	# or generate on-the-fly using some other command.
+}
+
+parseXML() {
+	# Convert the XML tree structure into multiple relations.
+	# Use XPath expressions to find record nodes
+	# and to find attributes inside them.
+	relpipe-in-xmltable \
+		--relation 'policy' \
+			--records '/busconfig/policy/allow|/busconfig/policy/deny' \
+			--attribute 'policy'           string 'name()' \
+			--attribute 'user'             string '../@user' \
+			--attribute 'context'          string '../@context' \
+			--attribute 'own'              string '@own' \
+			--attribute 'send_destination' string '@send_destination' \
+			--attribute 'send_interface'   string '@send_interface' \
+			--attribute 'send_member'      string '@send_member' \
+		--relation 'limit' \
+			--records '/busconfig/limit' \
+			--attribute 'name'             string '@name' \
+			--attribute 'value'            integer '.'
+}
+
+filterRecords() {
+	# Use native AWK command (called from relpipe-tr-awk)
+	# with all its power to filter the records.
+	# Work with named fields instead of numbered columns.
+	relpipe-tr-awk \
+		--relation "policy" \
+		--where 'policy == "allow" && user != "root"'
+
+	# Of course, we can do the same using SQL:
+	# relpipe-tr-sql \
+	#	--relation "policy" \
+	#		"SELECT * FROM policy WHERE policy = 'allow' AND user <> 'root'"
+	#	--copy 'limit'
+
+	# Or using Guile (Scheme):
+	# relpipe-tr-guile \
+	#	--relation policy \
+	#	--where '(and (string= $policy "allow") (not (string= $user "root")) )'
+}
+
+formatOutput() {
+	relpipe-out-tabular
+	# Or generate some other format:
+	# relpipe-out-ods       # spreadsheet for e.g. LibreOffice
+	# relpipe-out-xml       # XML e.g. for further XSLT or XQuery processing
+	# relpipe-out-recfile   # recfile for further GNU Recutils processing
+	# relpipe-out-asn1      # ASN.1 BER for the telco guys
+	# relpipe-out-gui       # display data in a GUI window
+	# etc.
+}
+
+# put the whole pipeline together:
+getXML | parseXML | filterRecords | formatOutput