diff --git a/pmap.c b/pmap.c
index d21517ae..d24fc663 100644
--- a/pmap.c
+++ b/pmap.c
@@ -994,6 +994,9 @@ int main(int argc, char **argv)
 	textdomain(PACKAGE);
 	atexit(close_stdout);
 
+	if (argc < 2)
+		usage(stderr);
+
 	while ((c = getopt_long(argc, argv, "xXrdqA:hVcC:nN:p", longopts, NULL)) != -1)
 		switch (c) {
 		case 'x':
diff --git a/testsuite/pmap.test/pmap.exp b/testsuite/pmap.test/pmap.exp
index eac9483c..ffbdb4f6 100644
--- a/testsuite/pmap.test/pmap.exp
+++ b/testsuite/pmap.test/pmap.exp
@@ -21,8 +21,8 @@ set pmap_ext_footer "\[ -\]+\\s+total kB\\s+\\d+(\\s+\[\\d-\]+){2,3}\\s*\$"
 
 set test "pmap with no arguments"
 spawn $pmap
-expect_pass "$test" "^\(lt-\)\?pmap: argument missing"
-#expect_pass "$test" "^Usage: pmap \\\[-x | -d\\\] \\\[-q\\\] \\\[-A low,high\\\] pid\\.\\.\\.\\s+-x\\s+show details\\s+-d\\s+show offset and device number\\s+-q\\s+quiet; less header/footer info\\s+-V\\s+show the version number\\s+-A\\s+limit results to the given range\\s*"
+#expect_pass "$test" "^\(lt-\)\?pmap: argument missing"
+expect_pass "$test" "Usage:\\s+\(lt-\)?pmap \\\[options\\\] pid \\\[pid \.\.\.\\\]"
 
 set test "pmap standard output"
 spawn $pmap $mypid