Funcții IO directe
 
Cuprins
- dio_close — Closes the file descriptor given by fd
 - dio_fcntl — Performs a c library fcntl on fd
 - dio_open — Opens a file (creating it if necessary) at a lower level than the
   C library input/ouput stream functions allow.
 - dio_read — Reads bytes from a file descriptor
 - dio_seek — Seeks to pos on fd from whence
 - dio_stat — Gets stat information about the file descriptor fd
 - dio_tcsetattr — Sets terminal attributes and baud rate for a serial port
 - dio_truncate — Truncates file descriptor fd to offset bytes
 - dio_write — Writes data to fd with optional truncation at length