LWL - The Log Writer Library

LWL - The Log Writer Library


The Log Writer Library (LWL) is a collection of routines for writing logs messages to files from C programms. It is a portable and re-entrant library fully written from scratch in pure ANSI C. It is designed to offer for C programmers common routines for logging messages in a highly customisable way.

The current version is LWL-1.1.0. It was released on January 11, 2005.

You can download it from http://download.gna.org/lwl/.

LWL is free software distributed under the terms of the GNU General Public License.


LWL provides a modern Applications Programming Interface (API) for C programmers, while allowing wrappers to be written for very high level languages.

Further information can be found in the LWL Documentation.


The LWL Reference Manual is available online, in following formats:

Supported Platforms

LWL is developed on Debian GNU/Linux with gcc. It should build on any GNU/linux distribution with gcc. GDSL has been tested with success under the following distributions:

We require that LWL should build on any system with an ANSI C compiler, so if doesn't, that's a bug and we would love a patch!

Download it

You can download the latest version of the distribution from the following site:

CVS Access

You can also check out the very latest version via anonymous cvs. Here's how:

cvs -d:pserver:anonymous@cvs.gna.org:/cvs/lwl co lwl
Once you have it checked out, you can update it with cvs update.

You can also view the cvs archive via cvsweb.

Note: if you use anonymous CVS, you will need some GNU tools that usually only developers use, and which are not required to build GNU packages from tarballs. These are automake, autoconf, libtool, GNU m4, GNU make, and others which might escape me now. They all come with recent GNU/Linux distributions, and for other OSes they can be found at ftp://ftp.gnu.org/pub/gnu/

To begin the build process from a CVS checkout, start with:

which will prepare the package for compilation. You can then use ./configure and make in the usual way.

Mailing lists

There are several mailing lists available, These mailing lists are archived here,

To subscribe to the lwl-announce mailing list, go to http://mail.gna.org/listinfo/lwl-announce.

To subscribe to the lwl-general mailing list, go to http://mail.gna.org/listinfo/lwl-general.

Authors and Credits

This list of authors who have directly contributed to LWL is available in the AUTHORS file. The THANKS file also contains list of people who have contributed to LWL.


LWL is distributed under the terms of the GNU General Public License (GPL).

The reasons why LWL uses the GPL are described in the following articles:

Contact Information

If you have a problem, or have found a bug, please visit the Gna! LWL homepage at http://gna.org/projects/lwl/ to send a note to the authors.

Last modified: Fri May 27 12:00:38 CEST 2005