This module provides a more portable way of using operating system (OS) dependent functionality than importing an OS dependent built-in module like posix or nt.
This module searches for an OS dependent built-in module like
mac or posix and exports the same functions and data
as found there. The design of all Python's built-in OS dependent
modules is such that as long as the same functionality is available,
it uses the same interface; e.g., the function
os.stat(path) returns stat information about path in
the same format (which happens to have originated with the
Extensions peculiar to a particular OS are also available through the os module, but using them is of course a threat to portability!
Note that after the first time os is imported, there is no performance penalty in using functions from os instead of directly from the OS dependent built-in module, so there should be no reason not to use os!
The os module contains many functions and data values. The items below and in the following sub-sections are all available directly from the os module.
When exceptions are classes, this exception carries two attributes, errno and strerror. The first holds the value of the C errno variable, and the latter holds the corresponding error message from strerror(). For exceptions that involve a file system path (e.g. chdir() or unlink()), the exception instance will contain a third attribute, filename, which is the file name passed to the function.
When exceptions are strings, the string for the exception is
os.path.split(file)is equivalent to but more portable than
posixpath.split(file). Note that this is also a valid module: it may be imported directly as os.path.