Improve documentation of permanent local variables.

 variables.texi (Creating Buffer-Local): Explain the meaning of
 permanent local variables.

2 files changed, 7 insertions, 0 deletions

diff --git a/doc/lispref/ChangeLog b/doc/lispref/ChangeLog
index 664464acda2..1d95eaf678c 100644
--- a/doc/lispref/ChangeLog
+++ b/doc/lispref/ChangeLog
@@ -1,3 +1,8 @@
+2011-02-18  Eli Zaretskii  <eliz@gnu.org>
+
+        * variables.texi (Creating Buffer-Local): Explain the meaning of
+        permanent local variables.
+
 2011-02-18  Glenn Morris  <rgm@gnu.org>
 
         * keymaps.texi (Remapping Commands): Mention how to undo it.
diff --git a/doc/lispref/variables.texi b/doc/lispref/variables.texi
index 2baf3895822..18343b4dc85 100644
--- a/doc/lispref/variables.texi
+++ b/doc/lispref/variables.texi
@@ -1409,6 +1409,8 @@ subsequent major mode.  @xref{Hooks}.
 @cindex permanent local variable
 A buffer-local variable is @dfn{permanent} if the variable name (a
 symbol) has a @code{permanent-local} property that is non-@code{nil}.
+Such variables are unaffected by @code{kill-all-local-variables}, and
+their local bindings are therefore not cleared by changing major modes.
 Permanent locals are appropriate for data pertaining to where the file
 came from or how to save it, rather than with how to edit the contents.