#include <debug.h>
typedef int pid_t;
+#define PID_ERROR ((pid_t) -1)
void halt (void) NO_RETURN;
void exit (int status) NO_RETURN;
pid_t exec (const char *file);
int join (pid_t);
-bool create (const char *file);
+bool create (const char *file, unsigned initial_size);
bool remove (const char *file);
int open (const char *file);
int filesize (int fd);
int read (int fd, void *buffer, unsigned length);
int write (int fd, const void *buffer, unsigned length);
+void seek (int fd, unsigned position);
+unsigned tell (int fd);
void close (int fd);
bool mmap (int fd, void *addr, unsigned length);
bool munmap (void *addr, unsigned length);