test_uuidd: add comment

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/tests/helpers/test_uuidd.c b/tests/helpers/test_uuidd.c
index f098c4ac47d7b95eefd22631581ed2399f0dcb1f..1262e359d78d9c27a64aae0f8f2ce0d8dd3cf5d3 100644 (file)
--- a/tests/helpers/test_uuidd.c
+++ b/tests/helpers/test_uuidd.c
@@ -5,6 +5,23 @@
  *     SAP Technology Group
  *
  * Copyright (C) 2015 Karel Zak <kzak@redhat.com>
+ *
+ *
+ * The test heavily uses shared memory, to enlarge maximal size of shared
+ * segment use:
+ *
+ *     echo "4294967295" > /proc/sys/kernel/shmm
+ *
+ * The test is compiled against in-tree libuuid, if you want to test uuidd
+ * installed to the system then make sure that libuuid uses the same socket
+ * like the running uuidd. You can start the uuidd manually, for example:
+ *
+ *     uuidd --debug --no-fork --no-pid --socket /run/uuidd/request
+ *
+ * if the $localstatedir (as defined by build-system) is /run. If you want
+ * to overwrite the built-in default then use:
+ *
+ *     make uuidd uuidgen localstatedir=/var
  */
 #include <error.h>
 #include <libgen.h>