* ralloc.c: Since the users of the relocating allocation code

* ralloc.c: Since the users of the relocating allocation code
	handle memory exhaustion, it's better to return an error code to
	them than to call abort.
	(obtain): If we cannot allocate more memory, don't call
	abort.  Instead, return non-zero iff the allocation is successful.
	(get_more_space): If obtain fails, return zero.
	(get_bloc): Return zero if we can't allocate the new bloc.
	(r_alloc_sbrk): Return zero if we can't allocate more memory.
	(r_alloc): If we can't allocate more memory, set *PTR to zero and
	return zero.
	(r_re_alloc): If we can't allocate more memory, leave *PTR
	unchanged, and return zero.

	* ralloc.c (warnfunction): Renamed to warn_function; users changed.