20.3. Operations¶
20.3.1. Register and Lookup Name¶
The rtems_io_register
directive associates a name with the specified device
(i.e. major/minor number pair). Device names are typically registered as part
of the device driver initialization sequence. The rtems_io_lookup
directive is used to determine the major/minor number pair associated with the
specified device name. The use of these directives frees the application from
being dependent on the arbitrary assignment of major numbers in a particular
application. No device naming conventions are dictated by RTEMS.
20.3.2. Accessing an Device Driver¶
The I/O manager provides directives which enable the application program to
utilize device drivers in a standard manner. There is a direct correlation
between the RTEMS I/O manager directives rtems_io_initialize
,
rtems_io_open
, rtems_io_close
, rtems_io_read
, rtems_io_write
,
and rtems_io_control
and the underlying device driver entry points.