cpython/Doc/library/fnmatch.rst

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:mod:`fnmatch` --- Unix filename pattern matching
=================================================
.. module:: fnmatch
:synopsis: Unix shell style filename pattern matching.
**Source code:** :source:`Lib/fnmatch.py`
.. index:: single: filenames; wildcard expansion
.. index:: module: re
--------------
This module provides support for Unix shell-style wildcards, which are *not* the
same as regular expressions (which are documented in the :mod:`re` module). The
special characters used in shell-style wildcards are:
.. index::
single: * (asterisk); in glob-style wildcards
single: ? (question mark); in glob-style wildcards
single: [] (square brackets); in glob-style wildcards
single: ! (exclamation); in glob-style wildcards
single: - (minus); in glob-style wildcards
+------------+------------------------------------+
| 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 ``'?'``.
.. index:: module: glob
Note that the filename separator (``'/'`` on Unix) is *not* special to this
module. See module :mod:`glob` for pathname expansion (:mod:`glob` uses
:func:`.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 :func:`functools.lru_cache` with the *maxsize* of 32768 is used to
cache the compiled regex patterns in the following functions: :func:`fnmatch`,
:func:`fnmatchcase`, :func:`.filter`.
.. function:: fnmatch(filename, pattern)
Test whether the *filename* string matches the *pattern* string, returning
:const:`True` or :const:`False`. Both parameters are case-normalized
using :func:`os.path.normcase`. :func:`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)
.. function:: fnmatchcase(filename, pattern)
Test whether *filename* matches *pattern*, returning :const:`True` or
:const:`False`; the comparison is case-sensitive and does not apply
:func:`os.path.normcase`.
.. function:: filter(names, pattern)
Construct a list from those elements of the iterable *names* that match *pattern*. It is the same as
``[n for n in names if fnmatch(n, pattern)]``, but implemented more efficiently.
.. function:: translate(pattern)
Return the shell-style *pattern* converted to a regular expression for
using with :func:`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'>
.. seealso::
Module :mod:`glob`
Unix shell-style path expansion.