[Tuxnes-devel] Use of mmap ()

[W. M. P. <mi...@fl...>]

Could someone explain what mmap is being used for in emu.c:

/* allocate space for the ROM */
if ((r = (int) mmap(ROM, 0x300000,
		    PROT_READ | PROT_WRITE | PROT_EXEC,
		    MAP_FIXED | MAP_PRIVATE | MAP_ANON, -1, 0)) < 0) {
    perror("mmap");
    exit(1);
}

?

The comment makes me wonder why malloc was not used.  I am not familiar
with the MAP_ANON option.

Also, in mapper.h things like _RAM point to hard-coded addresses, in
this case 0x10000000.  Again, why is this done?  GNU as will assume that
undefined variables are, to use C's syntax, extern, so _RAM could just
be defined as a char * in mapper.c.

I'm trying to get the dynrec. code to lay nicely with my new emulator
interface.

-- 
Mike

:wq