Explain the copyright of the output.

2 files changed, 24 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 4867dc7..f38e259 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2008-05-06  Bruno Haible  <bruno@clisp.org>
+
+	* doc/gperf.texi (Output Copyright): New section.
+	Reported by Mike Ingrassia <michael.ingrassia@motorola.com> and
+	Karice McIntyre <Karice_McIntyre@ca.ibm.com>.
+
 2008-04-06  Bruno Haible  <bruno@clisp.org>
 
 	* tests/Makefile.in: Use "LC_ALL=C tr" instead of "tr".
diff --git a/doc/gperf.texi b/doc/gperf.texi
index 146a004..552e36e 100644
--- a/doc/gperf.texi
+++ b/doc/gperf.texi
@@ -130,6 +130,7 @@ High-Level Description of GNU @code{gperf}
 * Input Format::                Input Format to @code{gperf}
 * Output Format::               Output Format for Generated C Code with @code{gperf}
 * Binary Strings::              Use of NUL bytes
+* Output Copyright::            The Copyright of the Output.
 
 Input Format to @code{gperf}
 
@@ -287,6 +288,7 @@ efficiently identify their respective reserved keywords.
 * Input Format::                Input Format to @code{gperf}
 * Output Format::               Output Format for Generated C Code with @code{gperf}
 * Binary Strings::              Use of NUL bytes
+* Output Copyright::            The Copyright of the Output.
 @end menu
 
 The perfect hash function generator @code{gperf} reads a set of
@@ -840,7 +842,7 @@ with the various input and output options, and timing the resulting C
 code, you can determine the best option choices for different keyword
 set characteristics.
 
-@node Binary Strings,  , Output Format, Description
+@node Binary Strings, Output Copyright, Output Format, Description
 @section Use of NUL bytes
 @cindex NUL
 
@@ -865,6 +867,21 @@ generated by @code{gperf} will treat NUL like any other byte.
 Also, in this case the @samp{-c} option (or, equivalently, the
 @samp{%compare-strncmp} declaration) is ignored.
 
+@node Output Copyright,  , Binary Strings, Description
+@section The Copyright of the Output
+@cindex Copyright
+
+@code{gperf} is under GPL, but that does not cause the output produced
+by @code{gperf} to be under GPL.  The reason is that the output contains
+only small pieces of text that come directly from @code{gperf}'s source
+code -- only about 7 lines long, too small for being significant --, and
+therefore the output is not a ``derivative work'' of @code{gperf} (in the
+sense of U.S.@: copyright law).
+
+On the other hand, the output produced by @code{gperf} contains essentially
+all of the input file.  Therefore the output is under the same license, with
+the same copyright holder, as the input that was passed to @code{gperf}.
+
 @node Options, Bugs, Description, Top
 @chapter Invoking @code{gperf}