cpython/Doc/library/glob.rst

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:mod:`glob` --- Unix style pathname pattern expansion
=====================================================
.. module:: glob
:synopsis: Unix shell style pathname pattern expansion.
**Source code:** :source:`Lib/glob.py`
.. index:: single: filenames; pathname expansion
--------------
.. 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
single: . (dot); in glob-style wildcards
The :mod:`glob` module finds all the pathnames matching a specified pattern
according to the rules used by the Unix shell, although results are returned in
arbitrary order. No tilde expansion is done, but ``*``, ``?``, and character
ranges expressed with ``[]`` will be correctly matched. This is done by using
the :func:`os.scandir` and :func:`fnmatch.fnmatch` functions in concert, and
not by actually invoking a subshell.
Note that files beginning with a dot (``.``) can only be matched by
patterns that also start with a dot,
unlike :func:`fnmatch.fnmatch` or :func:`pathlib.Path.glob`.
(For tilde and shell variable expansion, use :func:`os.path.expanduser` and
:func:`os.path.expandvars`.)
For a literal match, wrap the meta-characters in brackets.
For example, ``'[?]'`` matches the character ``'?'``.
The :mod:`glob` module defines the following functions:
.. function:: glob(pathname, *, root_dir=None, dir_fd=None, recursive=False, \
include_hidden=False)
Return a possibly empty list of path names that match *pathname*, which must be
a string containing a path specification. *pathname* can be either absolute
(like :file:`/usr/src/Python-1.5/Makefile`) or relative (like
:file:`../../Tools/\*/\*.gif`), and can contain shell-style wildcards. Broken
symlinks are included in the results (as in the shell). Whether or not the
results are sorted depends on the file system. If a file that satisfies
conditions is removed or added during the call of this function, whether
a path name for that file will be included is unspecified.
If *root_dir* is not ``None``, it should be a :term:`path-like object`
specifying the root directory for searching. It has the same effect on
:func:`glob` as changing the current directory before calling it. If
*pathname* is relative, the result will contain paths relative to
*root_dir*.
This function can support :ref:`paths relative to directory descriptors
<dir_fd>` with the *dir_fd* parameter.
.. index::
single: **; in glob-style wildcards
If *recursive* is true, the pattern "``**``" will match any files and zero or
more directories, subdirectories and symbolic links to directories. If the
pattern is followed by an :data:`os.sep` or :data:`os.altsep` then files will not
match.
If *include_hidden* is true, "``**``" pattern will match hidden directories.
.. audit-event:: glob.glob pathname,recursive glob.glob
.. audit-event:: glob.glob/2 pathname,recursive,root_dir,dir_fd glob.glob
.. note::
Using the "``**``" pattern in large directory trees may consume
an inordinate amount of time.
.. versionchanged:: 3.5
Support for recursive globs using "``**``".
.. versionchanged:: 3.10
Added the *root_dir* and *dir_fd* parameters.
.. versionchanged:: 3.11
Added the *include_hidden* parameter.
.. function:: iglob(pathname, *, root_dir=None, dir_fd=None, recursive=False, \
include_hidden=False)
Return an :term:`iterator` which yields the same values as :func:`glob`
without actually storing them all simultaneously.
.. audit-event:: glob.glob pathname,recursive glob.iglob
.. audit-event:: glob.glob/2 pathname,recursive,root_dir,dir_fd glob.iglob
.. versionchanged:: 3.5
Support for recursive globs using "``**``".
.. versionchanged:: 3.10
Added the *root_dir* and *dir_fd* parameters.
.. versionchanged:: 3.11
Added the *include_hidden* parameter.
.. function:: escape(pathname)
Escape all special characters (``'?'``, ``'*'`` and ``'['``).
This is useful if you want to match an arbitrary literal string that may
have special characters in it. Special characters in drive/UNC
sharepoints are not escaped, e.g. on Windows
``escape('//?/c:/Quo vadis?.txt')`` returns ``'//?/c:/Quo vadis[?].txt'``.
.. versionadded:: 3.4
.. function:: translate(pathname, *, recursive=False, include_hidden=False, seps=None)
Convert the given path specification to a regular expression for use with
:func:`re.match`. The path specification can contain shell-style wildcards.
For example:
>>> import glob, re
>>>
>>> regex = glob.translate('**/*.txt', recursive=True, include_hidden=True)
>>> regex
'(?s:(?:.+/)?[^/]*\\.txt)\\Z'
>>> reobj = re.compile(regex)
>>> reobj.match('foo/bar/baz.txt')
<re.Match object; span=(0, 15), match='foo/bar/baz.txt'>
Path separators and segments are meaningful to this function, unlike
:func:`fnmatch.translate`. By default wildcards do not match path
separators, and ``*`` pattern segments match precisely one path segment.
If *recursive* is true, the pattern segment "``**``" will match any number
of path segments. If "``**``" occurs in any position other than a full
pattern segment, :exc:`ValueError` is raised.
If *include_hidden* is true, wildcards can match path segments that start
with a dot (``.``).
A sequence of path separators may be supplied to the *seps* argument. If
not given, :data:`os.sep` and :data:`~os.altsep` (if available) are used.
.. seealso::
:meth:`pathlib.PurePath.match` and :meth:`pathlib.Path.glob` methods,
which call this function to implement pattern matching and globbing.
.. versionadded:: 3.13
Examples
--------
Consider a directory containing the following files:
:file:`1.gif`, :file:`2.txt`, :file:`card.gif` and a subdirectory :file:`sub`
which contains only the file :file:`3.txt`. :func:`glob` will produce
the following results. Notice how any leading components of the path are
preserved. ::
>>> import glob
>>> glob.glob('./[0-9].*')
['./1.gif', './2.txt']
>>> glob.glob('*.gif')
['1.gif', 'card.gif']
>>> glob.glob('?.gif')
['1.gif']
>>> glob.glob('**/*.txt', recursive=True)
['2.txt', 'sub/3.txt']
>>> glob.glob('./**/', recursive=True)
['./', './sub/']
If the directory contains files starting with ``.`` they won't be matched by
default. For example, consider a directory containing :file:`card.gif` and
:file:`.card.gif`::
>>> import glob
>>> glob.glob('*.gif')
['card.gif']
>>> glob.glob('.c*')
['.card.gif']
.. seealso::
The :mod:`fnmatch` module offers shell-style filename (not path) expansion.
.. seealso::
The :mod:`pathlib` module offers high-level path objects.