#include <u.h>#include <libc.h> extern	char	end[];static	char	*bloc = { end };extern	int	brk_(void*); enum{	Round	= 7}; intbrk(void *p){	uintptr bl; 	bl = ((uintptr)p + Round) & ~Round;	if(brk_((void*)bl) < 0)		return -1;	bloc = (char*)bl;	return 0;} void*sbrk(ulong n){	uintptr bl; 	bl = ((uintptr)bloc + Round) & ~Round;	if(brk_((void*)(bl+n)) < 0)		return (void*)-1;	bloc = (char*)bl + n;	return (void*)bl;}