Mention that rundir and vardir may be the same and what to do if they are.

diff --git a/INSTALL b/INSTALL
index 05ddf0e1910aba9b41686aca058325cbc9b2fc26..e55ea9ac3d3ac77314073bc4681bd8dd32d55acd 100644 (file)
--- a/INSTALL
+++ b/INSTALL
@@ -133,6 +133,9 @@ Directory and file names:
         will use the first existing directory in the following list:
            /var/run, /var/db, /var/lib, /var/adm, /usr/adm
        This directory should be cleared when the system reboots.
+       On systems that lack /var/run, the default rundir and vardir
+       may be the same.  In this case, only the ts directory inside
+       the rundir needs to be cleared at reboot time.
 
   --with-vardir=DIR
         Set the directory to be used for sudo-specific files that