//// Sbrk: Basic _sbrk implementation to make *printf work//#include<sys/stat.h>caddr_t_sbrk(intincr){externcharendasm("end");staticchar*heap_end;char*prev_heap_end;if(heap_end==0){heap_end=&end;}prev_heap_end=heap_end;heap_end+=incr;return(caddr_t)prev_heap_end;}