/* System Calls Remapping */#include <sys/stat.h>#include <stdlib.h>#include <errno.h>#undef errnoextern int errno;int _read (int file, char * ptr, int len) {  return 0;}int _lseek (int file, int ptr, int dir) {  return 0;}extern int putchar (int ch);int _write (int file, char * ptr, int len) {  int i;  for (i = 0; i < len; i++) putchar (*ptr++);  return len;}int _open (const char * path, int flags, ...) {  return -1;}int _close (int file) {  return -1;}void _exit (int n) {label:  goto label; /* endless loop */}int _kill (int n, int m) {  errno = EINVAL;  return(-1);}int _getpid (int n) {  return 1;}register char * stack_ptr asm ("sp");caddr_t _sbrk (int incr) {  extern char   end asm ("end");	/* Defined by the linker */  static char * heap_end;         char * prev_heap_end;  if (heap_end == NULL) heap_end = &end;  prev_heap_end = heap_end;    if (heap_end + incr > stack_ptr) {    _write (1, "_sbrk: Heap and stack collision\n", 32);    abort ();  }    heap_end += incr;  return (caddr_t) prev_heap_end;}int _fstat (int file, struct stat * st) {  st->st_mode = S_IFCHR;  return 0;}int _link (void) {  errno = EMLINK;  return -1;}int _unlink (void) {  errno = ENOENT;  return -1;}void _raise (void) {}int isatty (int fd) {  return 1;}