There is no clear borderline between both areas.
For example, Gnulib has a facility for generating the name of backup
-files. While this task is entirely at the application level---no
-standard specifies an API for it---the na@"{@dotless{i}}ve code has
+files. While this task is entirely at the application level --- no
+standard specifies an API for it --- the na@"{@dotless{i}}ve code has
some portability problems because on some platforms the length of file
name components is limited to 30 characters or so. Gnulib handles
that.
Similarly, Gnulib has a facility for executing a command in a
subprocess. It is at the same time a portability enhancement (it
-works on GNU/Unix and Windows, compared to the classical
+works on GNU, Unix, and Windows, compared to the classical
@code{fork()}/@code{exec()} which is not portable to Windows), as well
as an application aid: it takes care of redirecting stdin and/or
stdout if desired, and emits an error message if the subprocess
@section Modules
Gnulib is divided into modules. Every module implements a single
-facility. Modules can depend on other modules.
+facility. Modules can depend on other modules.
A module consists of a number of files and a module description. The
files are copied by @code{gnulib-tool} into the package that will use it,
the @file{m4/} subdirectory. Build scripts reside in the
@file{build-aux/} subdirectory.
-The module description contains the list of files---@code{gnulib-tool}
+The module description contains the list of files --- @code{gnulib-tool}
copies these files. It contains the module's
-dependencies---@code{gnulib-tool} installs them as well. It also
+dependencies --- @code{gnulib-tool} installs them as well. It also
contains the autoconf macro invocation (usually a single line or
-nothing at all)---@code{gnulib-tool} ensures this is invoked from the
+nothing at all) --- @code{gnulib-tool} ensures this is invoked from the
package's @file{configure.ac} file. And also a @file{Makefile.am}
-snippet---@code{gnulib-tool} collects these into a @file{Makefile.am}
+snippet --- @code{gnulib-tool} collects these into a @file{Makefile.am}
for the tailored Gnulib part. The module description and include file
specification are for documentation purposes; they are combined into
@file{MODULES.html}.
@item
It ensures consistency of the used autoconf macros and @file{Makefile.am}
rules with the source code. For example, source code which uses the
-@code{getopt_long} function---this is a common way to implement parsing
-of command line options in a way that complies with the GNU standards---
+@code{getopt_long} function --- this is a common way to implement parsing
+of command line options in a way that complies with the GNU standards ---
needs the source code (@file{lib/getopt.c} and others), the autoconf macro
which detects whether the system's libc already has this function (in
@file{m4/getopt.m4}), and a few @file{Makefile.am} lines that create the
@subsection Enhancements of ISO C or POSIX functions
These are sometimes POSIX functions with GNU extensions also found in
-glibc--examples: @samp{getopt}, @samp{fnmatch}---and often new
-APIs---for example, for all functions that allocate memory in one way
+glibc --- examples: @samp{getopt}, @samp{fnmatch} --- and often new
+APIs --- for example, for all functions that allocate memory in one way
or the other, we have variants which also include the error checking
against the out-of-memory condition.
@subsection Portable general use facilities
-Examples are a module for copying a file---the portability problems
+Examples are a module for copying a file --- the portability problems
relate to the copying of the file's modification time, access rights,
-and extended attributes---or a module for extracting the tail
-component of a file name---here the portability to Woe32 requires a
+and extended attributes --- or a module for extracting the tail
+component of a file name --- here the portability to Woe32 requires a
different API than the classical POSIX @code{basename} function.
@subsection Reusable application code
Most modules are under the GPL. Some, mostly modules which can
reasonably be used in libraries, are under LGPL. The source files
always say "GPL", but the real license specification is in the module
-description file.
+description file. If the module description file says "GPL", it currently
+means "GPLv2+" (GPLv2 or newer, at the licensee's choice); if it says "LGPL",
+it currently means "LGPLv2+" (LGPLv2 or newer, at the licensee's choice).
+
+More precisely, the license specification in the module description
+file applies to the files in @file{lib/} and @file{build-aux/}. Different
+licenses apply to files in special directories:
+
+@table @file
+@item modules/
+Module description files are under this copyright:
+
+@quotation
+Copyright @copyright{} 200X-200Y Free Software Foundation, Inc.@*
+Copying and distribution of this file, with or without modification,
+in any medium, are permitted without royalty provided the copyright
+notice and this notice are preserved.
+@end quotation
+
+@item m4/
+Autoconf macro files are under this copyright:
+
+@quotation
+Copyright @copyright{} 200X-200Y Free Software Foundation, Inc.@*
+This file is free software; the Free Software Foundation
+gives unlimited permission to copy and/or distribute it,
+with or without modifications, as long as this notice is preserved.
+@end quotation
+
+@item tests/
+If a license statement is not present in a test module, the test files are
+under GPL. Even if the corresponding source module is under LGPL, this is
+not a problem, since compiled tests are not installed by ``make install''.
+
+@item doc/
+Documentation files are under this copyright:
+
+@quotation
+Copyright @copyright{} 200X-200Y Free Software Foundation, Inc.@*
+Permission is granted to copy, distribute and/or modify this document
+under the terms of the GNU Free Documentation License, Version 1.1 or
+any later version published by the Free Software Foundation; with no
+Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
+Texts.
+@end quotation
+@end table
If you want to use some Gnulib modules under LGPL, you can do so by
passing the option @samp{--lgpl} to @code{gnulib-tool}. This will
projects / gnulib.git / blobdiff