This module provides access to operating system functionality that is
standardized by the C Standard and the POSIX standard (a thinly
disguised Unix interface).
Do not import this module directly. Instead, import the
module os, which provides a portable version of this
interface. On Unix, the os module provides a superset of
the posix interface. On non-Unix operating systems the
posix module is not available, but a subset is always
available through the os interface. Once os is
imported, there is no performance penalty in using it instead
of posix. In addition, os
provides some additional functionality, such as automatically calling
putenv() when an entry in os.environ is changed.
The descriptions below are very terse; refer to the corresponding
Unix manual (or POSIX documentation) entry for more information.
Arguments called path refer to a pathname given as a string.
Errors are reported as exceptions; the usual exceptions are given for
type errors, while errors reported by the system calls raise
error (a synonym for the standard exception
OSError), described below.
