11.1. Pathlib About

  • Python works with both relative and absolute path

  • Path separator \ (backslash) is used on Windows

  • Path separator / (slash) is used on *nix operating systems: Linux, macOS, BSD and other POSIX compliant OSes (excluding older versions of Windows)

  • In newer Windows versions both \ and / works the same

11.1.1. Relative Paths

  • Path is relative to currently running script

  • . - Current directory

  • .. - Parent directory

Current directory:

>>> FILE = 'myfile.txt'
>>> FILE = './myfile.txt'

>>> FILE = 'data/myfile.txt'
>>> FILE = './data/myfile.txt'

Parent directory:

>>> FILE = '../myfile.txt'
>>> FILE = '../data/myfile.txt'

>>> FILE = '../../myfile.txt'
>>> FILE = '../../data/myfile.txt'

11.1.2. Absolute Path

  • Absolute path on Windows starts with drive letter

  • Absolute path on *nix starts with root / dir

  • Absolute path include all entries in the directories hierarchy

Path on Linux:

>>> FILE = r'/home/mwatney/myfile.txt'

Path on macOS:

>>> FILE = r'/Users/mwatney/myfile.txt'

Path on Windows:

>>> FILE = 'C:\\Users\\mwatney\\myfile.txt'

11.1.3. Good Practices

  • Never hardcode paths, use constant as a file name or file path

  • Convention (singular form): FILE, FILENAME, FILEPATH, PATH

  • Convention (plural form): FILES, FILENAMES, FILEPATHS, PATHS

  • Note, that PATH is usually used for other purposes (sys.path or os.getenv('PATH'))

>>> FILE = '/tmp/myfile.txt'

>>> FILES = [
...     '/tmp/myfile.txt',
...     '/tmp/myfile.csv',
... ]

11.1.4. Escaping Characters

  • "\ " (backslash space) - escapes space

  • Note that in Python escapes in paths are not required

>>> FILE = '/tmp/my file.txt'

>>> FILE = r'/tmp/my file.txt'

>>> FILE = r'C:\Users\Admin\myfile.txt'
>>>
>>>
>>> repr(FILE)
"'C:\\\\Users\\\\Admin\\\\myfile.txt'"
>>>
>>> str(FILE)
'C:\\Users\\Admin\\myfile.txt'
>>>
>>> print(repr(FILE))
'C:\\Users\\Admin\\myfile.txt'
>>>
>>> print(FILE)
C:\Users\Admin\myfile.txt