autoupdate

diff --git a/doc/maintain.texi b/doc/maintain.texi
index cb6609884c0f1a2569bb35f4f7f176409f0fca88..6e0c3b1d9db02b472e690a0d736a04649b0ac4ae 100644 (file)
--- a/doc/maintain.texi
+++ b/doc/maintain.texi
@@ -5,7 +5,7 @@
 @c For double-sided printing, uncomment:
 @c @setchapternewpage odd
 @c This date is automagically updated when you save this file:
-@set lastupdate March 8, 2007
+@set lastupdate May 23, 2007
 @c %**end of header
 
 @dircategory GNU organization
@@ -446,6 +446,24 @@ and list them as the contributors of the code that you copied.  If all
 you did was copy it, not write it, then for copyright purposes you are
 @emph{not} one of the contributors of @emph{this} code.
 
+Especially when code has been released into the public domain, authors
+sometimes fail to write a license statement in each file.  In this
+case, please first be sure that all the authors of the code have
+disclaimed copyright interest.  Then, when copying the new files into
+your project, add a brief note at the beginning of the files recording
+the authors, the public domain status, and anything else relevant.
+
+On the other hand, when merging some public domain code into an
+existing file covered by the GPL (or LGPL or other free software
+license), there is no reason to indicate the pieces which are public
+domain.  The notice saying that the whole file is under the GPL (or
+other license) is legally sufficient.
+
+Using code that is released under a GPL-compatible free license,
+rather than being in the public domain, may require preserving
+copyright notices or other steps.  Of course, you should do what is
+needed.
+
 If you are maintaining an FSF-copyrighted package, please verify we
 have papers for the code you are copying, @emph{before} copying it.
 If you are copying from another FSF-copyrighted package, then we
@@ -462,6 +480,7 @@ doesn't mean it is ok to do without them.  If you cannot get papers
 for the code, you can only use it as an external library
 (@pxref{External Libraries}).
 
+
 @node Copyright Notices
 @section Copyright Notices
 @cindex copyright notices in program files