expp is a tool which transforms an XML file to another XML file, by using tags owned by a given namespace (xpp by default, but you can change it). This tags allow to handle macros, to affect value to variables ant to test their values, to include files, … In a glance, expp aims to be to XML what cpp is to C/C++.
The expp tool exclusively uses system and C/C++ standard libraries. It even has its own XML parser. So, no other package have to be installed for expp to work properly.
The expp tool is also used to test the Epeios XML library, and is also intended as an example to show how to use this library.
The Windows binary is included in the package. To obtain the linux binary, (or the cygwin one), simply unpack the package, and launch make in the obtained directory.
If the Windows binary doesn't work on your Windows system, please take a look to this page.
This tool (and the underlying libraries) are released under the GNU General Public License. This is the default licence, but, under some circumstances, other licences (with less restrictions, like GNU Lesser General Public License) are possible. Please contact me for more details.
The recognized tags are : define, expand, set, ifeq, and bloc. More details can be found on this page, on which you can also find an example of use.