Switch more function arguments docs to new-style.
diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index 9bed1ce..aa95d1d 100644
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -204,18 +204,17 @@
Return the current process's user id. Availability: Unix.
-.. function:: getenv(varname[, value])
+.. function:: getenv(key, default=None)
- Return the value of the environment variable *varname* if it exists, or *value*
- if it doesn't. *value* defaults to ``None``. Availability: most flavors of
- Unix, Windows.
+ Return the value of the environment variable *key* if it exists, or
+ *default* if it doesn't. Availability: most flavors of Unix, Windows.
-.. function:: putenv(varname, value)
+.. function:: putenv(key, value)
.. index:: single: environment variables; setting
- Set the environment variable named *varname* to the string *value*. Such
+ Set the environment variable named *key* to the string *value*. Such
changes to the environment affect subprocesses started with :func:`os.system`,
:func:`popen` or :func:`fork` and :func:`execv`. Availability: most flavors of
Unix, Windows.
@@ -326,11 +325,11 @@
Unix.
-.. function:: unsetenv(varname)
+.. function:: unsetenv(key)
.. index:: single: environment variables; deleting
- Unset (delete) the environment variable named *varname*. Such changes to the
+ Unset (delete) the environment variable named *key*. Such changes to the
environment affect subprocesses started with :func:`os.system`, :func:`popen` or
:func:`fork` and :func:`execv`. Availability: most flavors of Unix, Windows.
@@ -847,15 +846,14 @@
doesn't open the FIFO --- it just creates the rendezvous point.
-.. function:: mknod(filename[, mode=0o600, device])
+.. function:: mknod(filename[, mode=0o600[, device]])
Create a filesystem node (file, device special file or named pipe) named
- *filename*. *mode* specifies both the permissions to use and the type of node to
- be created, being combined (bitwise OR) with one of ``stat.S_IFREG``,
- ``stat.S_IFCHR``, ``stat.S_IFBLK``,
- and ``stat.S_IFIFO`` (those constants are available in :mod:`stat`).
- For ``stat.S_IFCHR`` and
- ``stat.S_IFBLK``, *device* defines the newly created device special file (probably using
+ *filename*. *mode* specifies both the permissions to use and the type of node
+ to be created, being combined (bitwise OR) with one of ``stat.S_IFREG``,
+ ``stat.S_IFCHR``, ``stat.S_IFBLK``, and ``stat.S_IFIFO`` (those constants are
+ available in :mod:`stat`). For ``stat.S_IFCHR`` and ``stat.S_IFBLK``,
+ *device* defines the newly created device special file (probably using
:func:`os.makedev`), otherwise it is ignored.
@@ -1123,7 +1121,7 @@
Availability: Unix, Windows.
-.. function:: walk(top[, topdown=True [, onerror=None[, followlinks=False]]])
+.. function:: walk(top, topdown=True, onerror=None, followlinks=False)
.. index::
single: directory; walking