lab 2 (probably working)

kern/include/syscall.h

@@ -30,7 +30,7 @@
 #ifndef _SYSCALL_H_
 #define _SYSCALL_H_
 
-
+#include <types.h>
 #include <cdefs.h> /* for __DEAD */
 struct trapframe; /* from <machine/trapframe.h> */
 
@@ -59,4 +59,9 @@ __DEAD void enter_new_process(int argc, userptr_t argv, userptr_t env,
 int sys_reboot(int code);
 int sys___time(userptr_t user_seconds, userptr_t user_nanoseconds);
 
+size_t sys_read(int filehandle, userptr_t buf, size_t size);
+size_t sys_write(int filehandle, const userptr_t buf, size_t size);
+
+void sys__exit(int status);
+
 #endif /* _SYSCALL_H_ */