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6.1.6 Miscellanenous System Data

The follow data values are used to support path manipulation operations. These are defined for all platforms.

Higher-level operations on pathnames are defined in the `os.path` module.

`curdir`
  The constant string used by the OS to refer to the current directory, e.g. `'.'` for POSIX or `':'` for the Macintosh.

`pardir`
  The constant string used by the OS to refer to the parent directory, e.g. `'..'` for POSIX or `'::'` for the Macintosh.

`sep`
  The character used by the OS to separate pathname components, e.g. "`/`" for POSIX or "`:`" for the Macintosh. Note that knowing this is not sufficient to be able to parse or concatenate pathnames -- use `os.path.split()` and `os.path.join()` -- but it is occasionally useful.

`altsep`
  An alternative character used by the OS to separate pathname components, or `None` if only one separator character exists. This is set to "`/`" on DOS and Windows systems where `sep` is a backslash.

`pathsep`
  The character conventionally used by the OS to separate search patch components (as in $PATH), e.g. "`:`" for POSIX or "`;`" for DOS and Windows.

`defpath`
  The default search path used by `exec*p*()` if the environment doesn't have a `'PATH'` key.

`linesep`
  The string used to separate (or, rather, terminate) lines on the current platform. This may be a single character, e.g. `'\n'` for POSIX or `'\r'` for MacOS, or multiple characters, e.g. `'\r\n'` for MS-DOS and MS Windows.