Error message when opening The Gimp

["Patrick Wiseman" <pwiseman@gmail.com>]

Why do I always get this message when I open The Gimp?

Unable to open a test swap file. To avoid data loss please check the
location and permissions of the swap directory defined in your
Preferences (currently "/tmp/gimp-
2.0").

There's no such directory.  If I create it, then restart The Gimp, all is well.  But the next time I get the error all over again.

Patrick