🚀 go-pugleaf

> From: olle@cb.uu.se (Olle Eriksson)
> gnuchess pl73 does not build on ultrix4.4 on a MIPS-decstation, neither 
> with gcc-2.6.0 or the native c-compiler

I have no problem building pl73 on Ultrix 4.2A, which is the latest 
version I have access to.

See the FAQ (just posted) for hints on building gnuchess on systems 
where you get the FIONREAD problem.  I include an extract below.

    --Tim

[24] I get an error message about FIONREAD when trying to build the GNU Chess
  book.  What do I do?

The message looks something like this:

> FIONREAD: Operation not supported on socket
> You probably have a non-ANSI <ioctl.h>; see README. -1 45 4004787f

If you are using gcc to compile, the solution to this error message is usually
to go to the GNU Chess Makefile, find the line that starts "CFLAGS=" (with no
# character in front of it), and append the flag "-traditional-cpp" to the end
of the line.  Then do

	rm dspcom*.o gnuan.o
	make
	make install

to rebuild gnuchess.

If you aren't using gcc, we don't really understand why this should happen,
but we do have a brute-force workaround: You can simply disable the gnuchess
feature that uses FIONREAD.  Find the two places in dspcom.c where the line
"#ifdef FIONREAD" occurs.  Change each of them to "#ifdef NOTDEF".  Then
recompile gnuchess.

With this code disabled, if you tell gnuchess to think on your time ("hard"
mode), you will have to type ^C to make it stop thinking when you want to make
your move.  The current version of XBoard does this automatically, so
disabling the code has no effect on XBoard.