diff --git a/tools/regression/lib/libutil/Makefile b/tools/regression/lib/libutil/Makefile
new file mode 100644
index 000000000000..05236eb23db5
--- /dev/null
+++ b/tools/regression/lib/libutil/Makefile
@@ -0,0 +1,12 @@
+# $FreeBSD$
+
+TESTS=	test-trimdomain test-trimdomain-nodomain
+CFLAGS+= -g -Wall -lutil
+
+.PHONY: tests
+tests: ${TESTS}
+	for p in ${TESTS}; do ${.OBJDIR}/$$p; done
+
+.PHONY: clean
+clean:
+	-rm -f ${TESTS}
diff --git a/tools/regression/lib/libutil/test-trimdomain-nodomain.c b/tools/regression/lib/libutil/test-trimdomain-nodomain.c
new file mode 100644
index 000000000000..344bc17e439e
--- /dev/null
+++ b/tools/regression/lib/libutil/test-trimdomain-nodomain.c
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2005 Brooks Davis. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <errno.h>
+#include <libutil.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#define TESTDOMAIN ""
+#define TESTHOST "testhost"
+#define TESTFQDN "testhost" TESTDOMAIN
+
+int failures = 0;
+int tests = 0;
+
+/*
+ * Evily override gethostname(3) so trimdomain always gets the same result.
+ * This makes the tests much easier to write and less likely to fail on
+ * oddly configured systems.
+ */
+int gethostname(char *name, size_t namelen)
+{
+	if (strlcpy(name, TESTFQDN, namelen) > namelen) {
+		errno = ENAMETOOLONG;
+		return (-1);
+	}
+	return (0);
+}
+
+void
+testit(const char *input, int hostsize, const char *output, const char *test)
+{
+	char *testhost;
+	const char *expected = (output == NULL) ? input : output;
+
+	testhost = strdup(input);
+	trimdomain(testhost, hostsize < 0 ? strlen(testhost) : hostsize);
+	tests++;
+	if (strcmp(testhost, expected) != 0) {
+		printf("not ok %d - %s\n", tests, test);
+		printf("# %s -> %s (expected %s)\n", input, testhost, expected);
+	} else
+		printf("ok %d - %s\n", tests, test);
+	free(testhost);
+	return;
+}
+
+int
+main (int argc, char **argv)
+{
+
+	printf("1..5\n");
+
+	testit(TESTFQDN, -1, TESTHOST, "self");
+	testit("XXX" TESTDOMAIN, -1, "XXX", "different host, same domain");
+	testit("XXX" TESTDOMAIN, 1, NULL, "short hostsize");
+	testit("bogus.example.net", -1, NULL, "arbitrary host");
+	testit("XXX." TESTFQDN, -1, NULL, "domain is local hostname");
+
+	return (0);
+}
diff --git a/tools/regression/lib/libutil/test-trimdomain-nodomain.t b/tools/regression/lib/libutil/test-trimdomain-nodomain.t
new file mode 100644
index 000000000000..8bdfd03be81b
--- /dev/null
+++ b/tools/regression/lib/libutil/test-trimdomain-nodomain.t
@@ -0,0 +1,10 @@
+#!/bin/sh
+# $FreeBSD$
+
+cd `dirname $0`
+
+executable=`basename $0 .t`
+
+make $executable 2>&1 > /dev/null
+
+exec ./$executable
diff --git a/tools/regression/lib/libutil/test-trimdomain.c b/tools/regression/lib/libutil/test-trimdomain.c
new file mode 100644
index 000000000000..d1c782380503
--- /dev/null
+++ b/tools/regression/lib/libutil/test-trimdomain.c
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2005 Brooks Davis. All rights reserved.
+ *
+ * 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 AUTHOR 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 AUTHOR 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <errno.h>
+#include <libutil.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#define TESTDOMAIN ".domain.example.com"
+#define TESTHOST "testhost"
+#define TESTFQDN "testhost" TESTDOMAIN
+
+int failures = 0;
+int tests = 0;
+
+/*
+ * Evily override gethostname(3) so trimdomain always gets the same result.
+ * This makes the tests much easier to write and less likely to fail on
+ * oddly configured systems.
+ */
+int gethostname(char *name, size_t namelen)
+{
+	if (strlcpy(name, TESTFQDN, namelen) > namelen) {
+		errno = ENAMETOOLONG;
+		return (-1);
+	}
+	return (0);
+}
+
+void
+testit(const char *input, int hostsize, const char *output, const char *test)
+{
+	char *testhost;
+	const char *expected = (output == NULL) ? input : output;
+
+	testhost = strdup(input);
+	trimdomain(testhost, hostsize < 0 ? strlen(testhost) : hostsize);
+	tests++;
+	if (strcmp(testhost, expected) != 0) {
+		printf("not ok %d - %s\n", tests, test);
+		printf("# %s -> %s (expected %s)\n", input, testhost, expected);
+	} else
+		printf("ok %d - %s\n", tests, test);
+	free(testhost);
+	return;
+}
+
+int
+main (int argc, char **argv)
+{
+
+	printf("1..5\n");
+
+	testit(TESTFQDN, -1, TESTHOST, "self");
+	testit("XXX" TESTDOMAIN, -1, "XXX", "different host, same domain");
+	testit("XXX" TESTDOMAIN, 1, NULL, "short hostsize");
+	testit("bogus.example.net", -1, NULL, "arbitrary host");
+	testit("XXX." TESTFQDN, -1, NULL, "domain is local hostname");
+
+	return (0);
+}
diff --git a/tools/regression/lib/libutil/test-trimdomain.t b/tools/regression/lib/libutil/test-trimdomain.t
new file mode 100644
index 000000000000..8bdfd03be81b
--- /dev/null
+++ b/tools/regression/lib/libutil/test-trimdomain.t
@@ -0,0 +1,10 @@
+#!/bin/sh
+# $FreeBSD$
+
+cd `dirname $0`
+
+executable=`basename $0 .t`
+
+make $executable 2>&1 > /dev/null
+
+exec ./$executable