fnmatch — Unix filename pattern matching — Python 3.11.15 documentation
Description: Source code: Lib/fnmatch.py This module provides support for Unix shell-style wildcards, which are not the same as regular expressions (which are documented in the re module). The special character...

# `fnmatch` — Unix filename pattern matching

Source code: Lib/fnmatch.py

This module provides support for Unix shell-style wildcards, which are not the same as regular expressions (which are documented in the `re` module). The special characters used in shell-style wildcards are:

Pattern | Meaning
--- | ---
`*` | matches everything
`?` | matches any single character
`[seq]` | matches any character in seq
`[!seq]` | matches any character not in seq

For a literal match, wrap the meta-characters in brackets. For example, `'[?]'` matches the character `'?'`.

Note that the filename separator (`'/'` on Unix) is not special to this module. See module `glob` for pathname expansion (`glob` uses `filter()` to match pathname segments). Similarly, filenames starting with a period are not special for this module, and are matched by the `*` and `?` patterns.

Also note that `functools.lru_cache()` with the maxsize of 32768 is used to cache the compiled regex patterns in the following functions: `fnmatch()`, `fnmatchcase()`, `filter()`.

fnmatch.fnmatch(name, pat)

  Test whether the filename string name matches the pattern string pat, returning `True` or `False`. Both parameters are case-normalized using `os.path.normcase()`. `fnmatchcase()` can be used to perform a case-sensitive comparison, regardless of whether that’s standard for the operating system.

  This example will print all file names in the current directory with the extension `.txt`:

      import fnmatch
      import os

      for file in os.listdir('.'):
          if fnmatch.fnmatch(file, '*.txt'):
              print(file)

fnmatch.fnmatchcase(name, pat)

  Test whether the filename string name matches the pattern string pat, returning `True` or `False`; the comparison is case-sensitive and does not apply `os.path.normcase()`.

fnmatch.filter(names, pat)

  Construct a list from those elements of the iterable names that match pattern pat. It is the same as `[n for n in names if fnmatch(n, pat)]`, but implemented more efficiently.

fnmatch.translate(pat)

  Return the shell-style pattern pat converted to a regular expression for using with `re.match()`.

  Example:

      >>> import fnmatch, re
      >>>
      >>> regex = fnmatch.translate('*.txt')
      >>> regex
      '(?s:.*\\.txt)\\Z'
      >>> reobj = re.compile(regex)
      >>> reobj.match('foobar.txt')
      <re.Match object; span=(0, 10), match='foobar.txt'>

See also

Module `glob`

  Unix shell-style path expansion.