Fails to guess system type in MacOS X

[Thomas Davie]

Hi, I have been having problems compiling GNU Prolog on my MacOS X based 
computer.  I have noticed this problem with quite a few applications 
that use the standard configure scripts, I think the most recent 
versions of them do support MacOS X.

Thanks

I enclose the output from the configure script so you can see what is 
going on.

[localhost:~/Desktop/gprolog-1.2.3/src] tatd100% ./configure
creating cache ./config.cache
checking for gcc... no
checking for cc... cc
checking whether the C compiler (cc  ) works... yes
checking whether the C compiler (cc  ) is a cross-compiler... no
checking whether we are using GNU C... yes
checking whether cc accepts -g... yes
checking for ranlib... ranlib
checking for Cygwin environment... no
checking for mingw32 environment... no
checking for executable suffix... no
checking whether make sets ${MAKE}... yes
checking for a BSD compatible install... /usr/bin/install -c
checking whether ln -s works... yes
checking host system type... configure: error: can not guess host type; 
you must specify one