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diff --git a/share/examples/flua/libjail.lua b/share/examples/flua/libjail.lua
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+++ b/share/examples/flua/libjail.lua
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+#!/usr/libexec/flua
+--[[
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2020, Ryan Moeller <freqlabs@FreeBSD.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+]]--
+
+jail = require("jail")
+ucl = require("ucl")
+
+name = "demo"
+
+local has_demo = false
+
+-- Make sure we don't have a demo jail to start with; "jid" and "name" are
+-- always present.
+for jparams in jail.list() do
+    if jparams["name"] == name then
+        has_demo = true
+        break
+    end
+end
+
+if not has_demo then
+    -- Create a persistent jail named "demo" with all other parameters default.
+    jid, err = jail.setparams(name, {persist = "true"}, jail.CREATE)
+    if not jid then
+        error(err)
+    end
+end
+
+-- Get a list of all known jail parameter names.
+allparams = jail.allparams()
+
+-- Get all the parameters of the jail we created.
+jid, res = jail.getparams(name, allparams)
+if not jid then
+    error(res)
+end
+
+-- Display the jail's parameters as a pretty-printed JSON object.
+print(ucl.to_json(res))
+
+-- Confirm that we still have it for now.
+has_demo = false
+for jparams in jail.list() do
+    if jparams["name"] == name then
+        has_demo = true
+        break
+    end
+end
+
+if not has_demo then
+    print("demo does not exist")
+end
+
+-- Update the "persist" parameter to "false" to remove the jail.
+jid, err = jail.setparams(name, {persist = "false"}, jail.UPDATE)
+if not jid then
+    error(err)
+end
+
+-- Verify that the jail is no longer on the system.
+local is_persistent = false
+has_demo = false
+for jparams in jail.list({"persist"}) do
+    if jparams["name"] == name then
+        has_demo = true
+        jid = jparams["jid"]
+        is_persistent = jparams["persist"] ~= "false"
+    end
+end
+
+-- In fact, it does remain until this process ends -- c'est la vie.
+if has_demo then
+    io.write("demo still exists, jid " .. jid .. ", ")
+    if is_persistent then
+        io.write("persistent\n")
+    else
+        io.write("not persistent\n")
+    end
+end