docs/library/uos: Create sections for distinct parts and document uname.

docs/library/uos.rst

@@ -6,11 +6,32 @@
 
 |see_cpython_module| :mod:`python:os`.
 
-The ``uos`` module contains functions for filesystem access and ``urandom``
-function.
+The ``uos`` module contains functions for filesystem access and mounting,
+terminal redirection and duplication, and the ``uname`` and ``urandom``
+functions.
 
-Functions
----------
+General functions
+-----------------
+
+.. function:: uname()
+
+   Return a tuple (possibly a named tuple) containing information about the
+   underlying machine and/or its operating system.  The tuple has five fields
+   in the following order, each of them being a string:
+
+        * ``sysname`` -- the name of the underlying system
+        * ``nodename`` -- the network name (can be the same as ``sysname``)
+        * ``release`` -- the version of the underlying system
+        * ``version`` -- the MicroPython version and build date
+        * ``machine`` -- an identifier for the underlying hardware (eg board, CPU)
+
+.. function:: urandom(n)
+
+   Return a bytes object with *n* random bytes. Whenever possible, it is
+   generated by the hardware random number generator.
+
+Filesystem access
+-----------------
 
 .. function:: chdir(path)
 
@@ -84,10 +105,8 @@ Functions
 
    Sync all filesystems.
 
-.. function:: urandom(n)
-
-   Return a bytes object with n random bytes. Whenever possible, it is
-   generated by the hardware random number generator.
+Terminal redirection and duplication
+------------------------------------
 
 .. function:: dupterm(stream_object, index=0)