[winGRASS] compiling native windows driver

[Glynn Clements]

Andreas Lange wrote:

> i got stuck with the compiling of the native windows driver.
> I strictly followed the description in
> src/display/devices/windows/INSTALL_WIN.
> (latest cygwin, W2K SP2, Intel PIII). I edited the head-file like the
> description, removed the OBJ.* directories and recompiled (Part 3.a of
> INSTALL_WIN). But this dies in function 'use_window':
> src/display/devices/XDRIVER/XDRIVER24/Graph_set.c:165: undefined
> reference to 'XScreenNumberOfScreen' (sorry, cut&paste does not work
> between Win and Linux). 

This appears to be related to a change which I made a few weeks back. 
The file src/display/devices/windows/libW11/X11/Xlib.h doesn't declare
this function, and src/display/devices/windows/libW11/w32/xlib.c
doesn't define it. The actual Xlib definition is:

	int XScreenNumberOfScreen (scr)
	    register Screen *scr;
	{
	    register Display *dpy = scr->display;
	    register Screen *dpyscr = dpy->screens;
	    register int i;
	
	    for (i = 0; i < dpy->nscreens; i++, dpyscr++) {
		if (scr == dpyscr) return i;
	    }
	    return -1;
	}

This ought to work for libW11, although it would probably suffice to
just use:

	#define XScreenNumberOfScreen(scr) 0

> Do i need the -D__W98__ on Windows 2000/NT ? This is not clear to me. 
> Has someone successfully compiled on W2K/NT?

You need -D__W98__ if either:

a) you are using libW11, or
b) you are building for Win95/98/ME

IOW, you don't need it if you are building for WinNT/2K/XP(?) and you
are using a genuine Xlib.

Basically, a) is because the libW11 emulation doesn't work following a
fork(), and b) is because Cygwin doesn't handle the fork() in
src/display/devices/lib/main.c correctly on Win95/98/ME.

-- 
Glynn Clements <glynn.clements at virgin.net>