Paths

Paths in Python always contains forward slashes, even in Windows.

os module

  • os.getcwd(): get current working directory
  • os.chdir(): change working directory, can take abosulte paths and relative paths
  • os.listdir(path): returns a list of the names of the entries in path except . and ...
  • os.stat(filename): returns a file’s metadata

os.path module

  • os.path.basename(path): get the last component of the path (filename)
  • os.path.dirname(path): get the directory name (everything before filename)
  • os.path.join(): take arbitrary number of parameters, join each part together with right slashes
  • os.path.expanduser(): expand ~ in the parameter passed into this function
  • os.path.split(path): return a tuple of (dirname, filename) for the file directory and the file name
  • os.path.splitext(filename): return a tuple of (name, extension) of a filename, filename can include its directory.
  • os.path.realpath(relative_path): return the absolute path of a relative path
  • os.path.exists(path): test for the existence of a file.
  • os.path.isfile(path), os.path.isdir(path), os.path.islink(path): test if a path is a file, a directory, or a symlink
  • os.path.getsize(path), os.path.getmtime(path): get the size and modification time

glob module

Use shell-like wildcards.

glob.glob(path_with_wildcards): returns a list of filenames (paths) matching this wildcard.

import glob

pyfiles = glob.glob('somedir/*.py')

File Name Match fnmatch

fnmatch module provides utilities to do file name match for strings like in shell. fnmatch(str, pattern) follows the same rule as the underlying OS for case-sensitivity, while fnmatchcase(str, pattern) is always case-sensitive.

shutil module

Supports high-level file operations such as copying and removal.

shutil.copy(src, dst) copies files.

Temporary Files and Directories

The tempfile module has a variety of functions for performing this task. To make an unnamed temporary file, use tempfile.TemporaryFile.

The first argument to TemporaryFile() is the file mode, which is usually w+t for text and w+b for binary.

It also has TemporaryDirectory.