hi all ...
i had a look at the autoconf documentation concerning the configure script ...
lots of the autoconf macros define certain defines ... anyway ... to use them, the code would have to be reworked ... e.g. HAVE_LIBFFTW3f would have to be used instead of USE_FFTW ...
this might be some work, but at least we would get rid of a lot of shell code in the autoconf script ...
for the linux part of it, i could try to do some cleanup, although i don't want to work of the win(mingw/cygwin) or osx part ...
cheers ... tim