The GNU Autoconf Archive is a collection of more than 500 macros for GNU Autoconf that have been contributed as free software by friendly supporters of the cause from all over the Internet. Every single one of those macros can be re-used without imposing any restrictions whatsoever on the licensing of the generated configure script. In particular, it is possible to use all those macros in configure scripts that are meant for non-free software. This policy is unusual for a Free Software Foundation project. The FSF firmly believes that software ought to be free, and software licenses like the GPL are specifically designed to ensure that derivative work based on free software must be free as well. In case of Autoconf, however, an exception has been made, because Autoconf is at such a pivotal position in the software development tool chain that the benefits from having this tool available as widely as possible outweigh the disadvantage that some authors may choose to use it, too, for proprietary software.
The best place to start exploring the Archive is the on-line documentation. There is also the Autoconf Archive home page at Savannah and a Github mirror.
Here are the compressed sources:
Here are the GPG detached signatures:
You can use either of the above signature files to verify that the corresponding file (without the .sig suffix) is intact. First, be sure to download both the .sig file and the corresponding tarball. Then, run a command like this:
gpg --verify autoconf-archive-2019.01.06.tar.xz.sig
If that command fails because you don't have the required public key, then run this command to import it:
gpg --keyserver keys.gnupg.net --recv-keys 99089D72
and rerun the gpg --verify command.
Copyright (c) 2019 Autoconf Archive Maintainers <autoconf-archive-maintainers@gnu.org>
The GNU Autoconf Archive is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
The GNU Autoconf Archive is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with the GNU Autoconf Archive. If not, see https://www.gnu.org/licenses/.