The emx libraries are not distributed under the GPL.  Linking an
application with the emx libraries does not cause the executable
to be covered by the GNU General Public License.  You are allowed
to change and copy the emx library sources if you keep the copyright
message intact.  If you improve the emx libraries, please send your
enhancements to the emx author (you should copyright your
enhancements similar to the existing emx libraries).