          = 0   // { ssize_t read(int fd, void *buf, size_t nbyte); }  SYS_WRITE                    = 0   // { ssize_t write(int fd, const void *buf, size_t nbyte); }  SYS_OPEN                     = 0   // { int open(char *path, int flags, int mode); }  SYS_CLOSE         