c-user: Split up IO manager

This makes it easier to automatically generate parts of the manager
documentation in the future.

Update #3993.

1 files changed, 26 insertions, 0 deletions

diff --git a/c-user/io/operations.rst b/c-user/io/operations.rst
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+.. SPDX-License-Identifier: CC-BY-SA-4.0
+
+.. Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR)
+
+Operations
+==========
+
+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.
+
+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.