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PROGRAM:

NAME

pathlib - pathlib Documentation

Manipulating filesystem paths as string objects can quickly become cumbersome: multiple
calls to os.path.join() or os.path.dirname(), etc. This module offers a set of classes
featuring all the common operations on paths in an easy, object-oriented way.

This module is best used with Python 3.2 or later, but it is also compatible with Python
2.7.

NOTE:
This module has been included in the Python 3.4 standard library after PEP 428
acceptance. You only need to install it for Python 3.3 or older.

SEE ALSO:
PEP 428: Rationale for the final pathlib design and API.

DOWNLOAD

Standalone releases are available on PyPI: http://pypi.python.org/pypi/pathlib/

Main development now takes place in the Python standard library: see the Python
developer's guide.

The maintenance repository for this standalone backport module can be found on BitBucket,
but activity is expected to be quite low: https://bitbucket.org/pitrou/pathlib/

HIGH-LEVEL VIEW

This module offers classes representing filesystem paths with semantics appropriate for
different operating systems. Path classes are divided between pure paths, which provide
purely computational operations without I/O, and concrete paths, which inherit from pure
paths but also provide I/O operations. [image]

If you've never used this module before or just aren't sure which class is right for your
task, Path is most likely what you need. It instantiates a concrete path for the platform
the code is running on.

Pure paths are useful in some special cases; for example:

1. If you want to manipulate Windows paths on a Unix machine (or vice versa). You cannot
instantiate a WindowsPath when running on Unix, but you can instantiate
PureWindowsPath.

2. You want to make sure that your code only manipulates paths without actually accessing
the OS. In this case, instantiating one of the pure classes may be useful since those
simply don't have any OS-accessing operations.

BASIC USE

Importing the module classes:

>>> from pathlib import *

Listing subdirectories:

>>> p = Path('.')
>>> [x for x in p.iterdir() if x.is_dir()]
[PosixPath('.hg'), PosixPath('docs'), PosixPath('dist'),
PosixPath('__pycache__'), PosixPath('build')]

Listing Python source files in this directory tree:

>>> list(p.glob('**/*.py'))
[PosixPath('test_pathlib.py'), PosixPath('setup.py'),
PosixPath('pathlib.py'), PosixPath('docs/conf.py'),
PosixPath('build/lib/pathlib.py')]

Navigating inside a directory tree:

>>> p = Path('/etc')
>>> q = p / 'init.d' / 'reboot'
>>> q
PosixPath('/etc/init.d/reboot')
>>> q.resolve()
PosixPath('/etc/rc.d/init.d/halt')

Querying path properties:

>>> q.exists()
True
>>> q.is_dir()
False

Opening a file:

>>> with q.open() as f: f.readline()
...
'#!/bin/bash\n'

PURE PATHS

Pure path objects provide path-handling operations which don't actually access a
filesystem. There are three ways to access these classes, which we also call flavours:

class pathlib.PurePath(*pathsegments)
A generic class that represents the system's path flavour (instantiating it creates
either a PurePosixPath or a PureWindowsPath):

>>> PurePath('setup.py') # Running on a Unix machine
PurePosixPath('setup.py')

Each element of pathsegments can be either a string or bytes object representing a
path segment; it can also be another path object:

>>> PurePath('foo', 'some/path', 'bar')
PurePosixPath('foo/some/path/bar')
>>> PurePath(Path('foo'), Path('bar'))
PurePosixPath('foo/bar')

When pathsegments is empty, the current directory is assumed:

>>> PurePath()
PurePosixPath('.')

When several absolute paths are given, the last is taken as an anchor (mimicking
os.path.join()'s behaviour):

>>> PurePath('/etc', '/usr', 'lib64')
PurePosixPath('/usr/lib64')
>>> PureWindowsPath('c:/Windows', 'd:bar')
PureWindowsPath('d:bar')

However, in a Windows path, changing the local root doesn't discard the previous
drive setting:

>>> PureWindowsPath('c:/Windows', '/Program Files')
PureWindowsPath('c:/Program Files')

Spurious slashes and single dots are collapsed, but double dots ('..') are not,
since this would change the meaning of a path in the face of symbolic links:

>>> PurePath('foo//bar')
PurePosixPath('foo/bar')
>>> PurePath('foo/./bar')
PurePosixPath('foo/bar')
>>> PurePath('foo/../bar')
PurePosixPath('foo/../bar')

(a naïve approach would make PurePosixPath('foo/../bar') equivalent to
PurePosixPath('bar'), which is wrong if foo is a symbolic link to another
directory)

class pathlib.PurePosixPath(*pathsegments)
A subclass of PurePath, this path flavour represents non-Windows filesystem paths:

>>> PurePosixPath('/etc')
PurePosixPath('/etc')

pathsegments is specified similarly to PurePath.

class pathlib.PureWindowsPath(*pathsegments)
A subclass of PurePath, this path flavour represents Windows filesystem paths:

>>> PureWindowsPath('c:/Program Files/')
PureWindowsPath('c:/Program Files')

pathsegments is specified similarly to PurePath.

Regardless of the system you're running on, you can instantiate all of these classes,
since they don't provide any operation that does system calls.

General properties
Paths are immutable and hashable. Paths of a same flavour are comparable and orderable.
These properties respect the flavour's case-folding semantics:

>>> PurePosixPath('foo') == PurePosixPath('FOO')
False
>>> PureWindowsPath('foo') == PureWindowsPath('FOO')
True
>>> PureWindowsPath('FOO') in { PureWindowsPath('foo') }
True
>>> PureWindowsPath('C:') < PureWindowsPath('d:')
True

Paths of a different flavour compare unequal and cannot be ordered:

>>> PureWindowsPath('foo') == PurePosixPath('foo')
False
>>> PureWindowsPath('foo') < PurePosixPath('foo')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: unorderable types: PureWindowsPath() < PurePosixPath()

Operators
The slash operator helps create child paths, similarly to os.path.join:

>>> p = PurePath('/etc')
>>> p
PurePosixPath('/etc')
>>> p / 'init.d' / 'apache2'
PurePosixPath('/etc/init.d/apache2')
>>> q = PurePath('bin')
>>> '/usr' / q
PurePosixPath('/usr/bin')

The string representation of a path is the raw filesystem path itself (in native form,
e.g. with backslashes under Windows), which you can pass to any function taking a file
path as a string:

>>> p = PurePath('/etc')
>>> str(p)
'/etc'
>>> p = PureWindowsPath('c:/Program Files')
>>> str(p)
'c:\\Program Files'

Similarly, calling bytes on a path gives the raw filesystem path as a bytes object, as
encoded by os.fsencode:

>>> bytes(p)
b'/etc'

Accessing individual parts
To access the individual "parts" (components) of a path, use the following property:

PurePath.parts
A tuple giving access to the path's various components:

>>> p = PurePath('/usr/bin/python3')
>>> p.parts
('/', 'usr', 'bin', 'python3')

>>> p = PureWindowsPath('c:/Program Files/PSF')
>>> p.parts
('c:\\', 'Program Files', 'PSF')

(note how the drive and local root are regrouped in a single part)

Methods and properties
Pure paths provide the following methods and properties:

PurePath.drive
A string representing the drive letter or name, if any:

>>> PureWindowsPath('c:/Program Files/').drive
'c:'
>>> PureWindowsPath('/Program Files/').drive
''
>>> PurePosixPath('/etc').drive
''

UNC shares are also considered drives:

>>> PureWindowsPath('//host/share/foo.txt').drive
'\\\\host\\share'

PurePath.root
A string representing the (local or global) root, if any:

>>> PureWindowsPath('c:/Program Files/').root
'\\'
>>> PureWindowsPath('c:Program Files/').root
''
>>> PurePosixPath('/etc').root
'/'

UNC shares always have a root:

>>> PureWindowsPath('//host/share').root
'\\'

PurePath.anchor
The concatenation of the drive and root:

>>> PureWindowsPath('c:/Program Files/').anchor
'c:\\'
>>> PureWindowsPath('c:Program Files/').anchor
'c:'
>>> PurePosixPath('/etc').anchor
'/'
>>> PureWindowsPath('//host/share').anchor
'\\\\host\\share\\'

PurePath.parents
An immutable sequence providing access to the logical ancestors of the path:

>>> p = PureWindowsPath('c:/foo/bar/setup.py')
>>> p.parents[0]
PureWindowsPath('c:/foo/bar')
>>> p.parents[1]
PureWindowsPath('c:/foo')
>>> p.parents[2]
PureWindowsPath('c:/')

PurePath.parent
The logical parent of the path:

>>> p = PurePosixPath('/a/b/c/d')
>>> p.parent
PurePosixPath('/a/b/c')

You cannot go past an anchor, or empty path:

>>> p = PurePosixPath('/')
>>> p.parent
PurePosixPath('/')
>>> p = PurePosixPath('.')
>>> p.parent
PurePosixPath('.')

NOTE:
This is a purely lexical operation, hence the following behaviour:

>>> p = PurePosixPath('foo/..')
>>> p.parent
PurePosixPath('foo')

If you want to walk an arbitrary filesystem path upwards, it is recommended to
first call Path.resolve() so as to resolve symlinks and eliminate ".."
components.

PurePath.name
A string representing the final path component, excluding the drive and root, if
any:

>>> PurePosixPath('my/library/setup.py').name
'setup.py'

UNC drive names are not considered:

>>> PureWindowsPath('//some/share/setup.py').name
'setup.py'
>>> PureWindowsPath('//some/share').name
''

PurePath.suffix
The file extension of the final component, if any:

>>> PurePosixPath('my/library/setup.py').suffix
'.py'
>>> PurePosixPath('my/library.tar.gz').suffix
'.gz'
>>> PurePosixPath('my/library').suffix
''

PurePath.suffixes
A list of the path's file extensions:

>>> PurePosixPath('my/library.tar.gar').suffixes
['.tar', '.gar']
>>> PurePosixPath('my/library.tar.gz').suffixes
['.tar', '.gz']
>>> PurePosixPath('my/library').suffixes
[]

PurePath.stem
The final path component, without its suffix:

>>> PurePosixPath('my/library.tar.gz').stem
'library.tar'
>>> PurePosixPath('my/library.tar').stem
'library'
>>> PurePosixPath('my/library').stem
'library'

PurePath.as_posix()
Return a string representation of the path with forward slashes (/):

>>> p = PureWindowsPath('c:\\windows')
>>> str(p)
'c:\\windows'
>>> p.as_posix()
'c:/windows'

PurePath.as_uri()
Represent the path as a file URI. ValueError is raised if the path isn't absolute.

>>> p = PurePosixPath('/etc/passwd')
>>> p.as_uri()
'file:///etc/passwd'
>>> p = PureWindowsPath('c:/Windows')
>>> p.as_uri()
'file:///c:/Windows'

PurePath.is_absolute()
Return whether the path is absolute or not. A path is considered absolute if it
has both a root and (if the flavour allows) a drive:

>>> PurePosixPath('/a/b').is_absolute()
True
>>> PurePosixPath('a/b').is_absolute()
False

>>> PureWindowsPath('c:/a/b').is_absolute()
True
>>> PureWindowsPath('/a/b').is_absolute()
False
>>> PureWindowsPath('c:').is_absolute()
False
>>> PureWindowsPath('//some/share').is_absolute()
True

PurePath.is_reserved()
With PureWindowsPath, return True if the path is considered reserved under Windows,
False otherwise. With PurePosixPath, False is always returned.

>>> PureWindowsPath('nul').is_reserved()
True
>>> PurePosixPath('nul').is_reserved()
False

File system calls on reserved paths can fail mysteriously or have unintended
effects.

PurePath.joinpath(*other)
Calling this method is equivalent to combining the path with each of the other
arguments in turn:

>>> PurePosixPath('/etc').joinpath('passwd')
PurePosixPath('/etc/passwd')
>>> PurePosixPath('/etc').joinpath(PurePosixPath('passwd'))
PurePosixPath('/etc/passwd')
>>> PurePosixPath('/etc').joinpath('init.d', 'apache2')
PurePosixPath('/etc/init.d/apache2')
>>> PureWindowsPath('c:').joinpath('/Program Files')
PureWindowsPath('c:/Program Files')

PurePath.match(pattern)
Match this path against the provided glob-style pattern. Return True if matching
is successful, False otherwise.

If pattern is relative, the path can be either relative or absolute, and matching
is done from the right:

>>> PurePath('a/b.py').match('*.py')
True
>>> PurePath('/a/b/c.py').match('b/*.py')
True
>>> PurePath('/a/b/c.py').match('a/*.py')
False

If pattern is absolute, the path must be absolute, and the whole path must match:

>>> PurePath('/a.py').match('/*.py')
True
>>> PurePath('a/b.py').match('/*.py')
False

As with other methods, case-sensitivity is observed:

>>> PureWindowsPath('b.py').match('*.PY')
True

PurePath.relative_to(*other)
Compute a version of this path relative to the path represented by other. If it's
impossible, ValueError is raised:

>>> p = PurePosixPath('/etc/passwd')
>>> p.relative_to('/')
PurePosixPath('etc/passwd')
>>> p.relative_to('/etc')
PurePosixPath('passwd')
>>> p.relative_to('/usr')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "pathlib.py", line 694, in relative_to
.format(str(self), str(formatted)))
ValueError: '/etc/passwd' does not start with '/usr'

PurePath.with_name(name)
Return a new path with the name changed. If the original path doesn't have a name,
ValueError is raised:

>>> p = PureWindowsPath('c:/Downloads/pathlib.tar.gz')
>>> p.with_name('setup.py')
PureWindowsPath('c:/Downloads/setup.py')
>>> p = PureWindowsPath('c:/')
>>> p.with_name('setup.py')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/home/antoine/cpython/default/Lib/pathlib.py", line 751, in with_name
raise ValueError("%r has an empty name" % (self,))
ValueError: PureWindowsPath('c:/') has an empty name

PurePath.with_suffix(suffix)
Return a new path with the suffix changed. If the original path doesn't have a
suffix, the new suffix is appended instead:

>>> p = PureWindowsPath('c:/Downloads/pathlib.tar.gz')
>>> p.with_suffix('.bz2')
PureWindowsPath('c:/Downloads/pathlib.tar.bz2')
>>> p = PureWindowsPath('README')
>>> p.with_suffix('.txt')
PureWindowsPath('README.txt')

CONCRETE PATHS

Concrete paths are subclasses of the pure path classes. In addition to operations
provided by the latter, they also provide methods to do system calls on path objects.
There are three ways to instantiate concrete paths:

class pathlib.Path(*pathsegments)
A subclass of PurePath, this class represents concrete paths of the system's path
flavour (instantiating it creates either a PosixPath or a WindowsPath):

>>> Path('setup.py')
PosixPath('setup.py')

pathsegments is specified similarly to PurePath.

class pathlib.PosixPath(*pathsegments)
A subclass of Path and PurePosixPath, this class represents concrete non-Windows
filesystem paths:

>>> PosixPath('/etc')
PosixPath('/etc')

pathsegments is specified similarly to PurePath.

class pathlib.WindowsPath(*pathsegments)
A subclass of Path and PureWindowsPath, this class represents concrete Windows
filesystem paths:

>>> WindowsPath('c:/Program Files/')
WindowsPath('c:/Program Files')

pathsegments is specified similarly to PurePath.

You can only instantiate the class flavour that corresponds to your system (allowing
system calls on non-compatible path flavours could lead to bugs or failures in your
application):

>>> import os
>>> os.name
'posix'
>>> Path('setup.py')
PosixPath('setup.py')
>>> PosixPath('setup.py')
PosixPath('setup.py')
>>> WindowsPath('setup.py')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "pathlib.py", line 798, in __new__
% (cls.__name__,))
NotImplementedError: cannot instantiate 'WindowsPath' on your system

Methods
Concrete paths provide the following methods in addition to pure paths methods. Many of
these methods can raise an OSError if a system call fails (for example because the path
doesn't exist):

classmethod Path.cwd()
Return a new path object representing the current directory (as returned by
os.getcwd()):

>>> Path.cwd()
PosixPath('/home/antoine/pathlib')

Path.stat()
Return information about this path (similarly to os.stat()). The result is looked
up at each call to this method.

>>> p = Path('setup.py')
>>> p.stat().st_size
956
>>> p.stat().st_mtime
1327883547.852554

Path.chmod(mode)
Change the file mode and permissions, like os.chmod():

>>> p = Path('setup.py')
>>> p.stat().st_mode
33277
>>> p.chmod(0o444)
>>> p.stat().st_mode
33060

Path.exists()
Whether the path points to an existing file or directory:

>>> from pathlib import *
>>> Path('.').exists()
True
>>> Path('setup.py').exists()
True
>>> Path('/etc').exists()
True
>>> Path('nonexistentfile').exists()
False

Path.glob(pattern)
Glob the given pattern in the directory represented by this path, yielding all
matching files (of any kind):

>>> sorted(Path('.').glob('*.py'))
[PosixPath('pathlib.py'), PosixPath('setup.py'), PosixPath('test_pathlib.py')]
>>> sorted(Path('.').glob('*/*.py'))
[PosixPath('docs/conf.py')]

The "**" pattern means "this directory and all subdirectories, recursively". In
other words, it enables recursive globbing:

>>> sorted(Path('.').glob('**/*.py'))
[PosixPath('build/lib/pathlib.py'),
PosixPath('docs/conf.py'),
PosixPath('pathlib.py'),
PosixPath('setup.py'),
PosixPath('test_pathlib.py')]

NOTE:
Using the "**" pattern in large directory trees may consume an inordinate amount
of time.

Path.group()
Return the name of the group owning the file. KeyError is raised if the file's gid
isn't found in the system database.

Path.is_dir()
Return True if the path points to a directory (or a symbolic link pointing to a
directory), False if it points to another kind of file.

False is also returned if the path doesn't exist or is a broken symlink; other
errors (such as permission errors) are propagated.

Path.is_file()
Return True if the path points to a regular file (or a symbolic link pointing to a
regular file), False if it points to another kind of file.

False is also returned if the path doesn't exist or is a broken symlink; other
errors (such as permission errors) are propagated.

Path.is_symlink()
Return True if the path points to a symbolic link, False otherwise.

False is also returned if the path doesn't exist; other errors (such as permission
errors) are propagated.

Path.is_socket()
Return True if the path points to a Unix socket (or a symbolic link pointing to a
Unix socket), False if it points to another kind of file.

False is also returned if the path doesn't exist or is a broken symlink; other
errors (such as permission errors) are propagated.

Path.is_fifo()
Return True if the path points to a FIFO (or a symbolic link pointing to a FIFO),
False if it points to another kind of file.

False is also returned if the path doesn't exist or is a broken symlink; other
errors (such as permission errors) are propagated.

Path.is_block_device()
Return True if the path points to a block device (or a symbolic link pointing to a
block device), False if it points to another kind of file.

False is also returned if the path doesn't exist or is a broken symlink; other
errors (such as permission errors) are propagated.

Path.is_char_device()
Return True if the path points to a character device (or a symbolic link pointing
to a character device), False if it points to another kind of file.

False is also returned if the path doesn't exist or is a broken symlink; other
errors (such as permission errors) are propagated.

Path.iterdir()
When the path points to a directory, yield path objects of the directory contents:

>>> p = Path('docs')
>>> for child in p.iterdir(): child
...
PosixPath('docs/conf.py')
PosixPath('docs/_templates')
PosixPath('docs/make.bat')
PosixPath('docs/index.rst')
PosixPath('docs/_build')
PosixPath('docs/_static')
PosixPath('docs/Makefile')

Path.lchmod(mode)
Like Path.chmod() but, if the path points to a symbolic link, the symbolic link's
mode is changed rather than its target's.

Path.lstat()
Like Path.stat() but, if the path points to a symbolic link, return the symbolic
link's information rather than its target's.

Path.mkdir(mode=0o777, parents=False)
Create a new directory at this given path. If mode is given, it is combined with
the process' umask value to determine the file mode and access flags. If the path
already exists, OSError is raised.

If parents is true, any missing parents of this path are created as needed; they
are created with the default permissions without taking mode into account
(mimicking the POSIX mkdir -p command).

If parents is false (the default), a missing parent raises OSError.

Path.open(mode='r', buffering=-1, encoding=None, errors=None, newline=None)
Open the file pointed to by the path, like the built-in open() function does:

>>> p = Path('setup.py')
>>> with p.open() as f:
... f.readline()
...
'#!/usr/bin/env python3\n'

Path.owner()
Return the name of the user owning the file. KeyError is raised if the file's uid
isn't found in the system database.

Path.rename(target)
Rename this file or directory to the given target. target can be either a string
or another path object:

>>> p = Path('foo')
>>> p.open('w').write('some text')
9
>>> target = Path('bar')
>>> p.rename(target)
>>> target.open().read()
'some text'

Path.replace(target)
Rename this file or directory to the given target. If target points to an existing
file or directory, it will be unconditionally replaced.

This method is only available with Python 3.3; it will raise NotImplementedError on
previous Python versions.

Path.resolve()
Make the path absolute, resolving any symlinks. A new path object is returned:

>>> p = Path()
>>> p
PosixPath('.')
>>> p.resolve()
PosixPath('/home/antoine/pathlib')

".." components are also eliminated (this is the only method to do so):

>>> p = Path('docs/../setup.py')
>>> p.resolve()
PosixPath('/home/antoine/pathlib/setup.py')

If the path doesn't exist, an OSError is raised. If an infinite loop is
encountered along the resolution path, RuntimeError is raised.

Path.rglob(pattern)
This is like calling glob() with "**" added in front of the given pattern:

>>> sorted(Path().rglob("*.py"))
[PosixPath('build/lib/pathlib.py'),
PosixPath('docs/conf.py'),
PosixPath('pathlib.py'),
PosixPath('setup.py'),
PosixPath('test_pathlib.py')]

Path.rmdir()
Remove this directory. The directory must be empty.

Path.symlink_to(target, target_is_directory=False)
Make this path a symbolic link to target. Under Windows, target_is_directory must
be true (default False) if the link's target is a directory. Under POSIX,
target_is_directory's value is ignored.

>>> p = Path('mylink')
>>> p.symlink_to('setup.py')
>>> p.resolve()
PosixPath('/home/antoine/pathlib/setup.py')
>>> p.stat().st_size
956
>>> p.lstat().st_size
8

NOTE:
The order of arguments (link, target) is the reverse of os.symlink()'s.

Path.touch(mode=0o777, exist_ok=True)
Create a file at this given path. If mode is given, it is combined with the
process' umask value to determine the file mode and access flags. If the file
already exists, the function succeeds if exist_ok is true (and its modification
time is updated to the current time), otherwise OSError is raised.

Path.unlink()
Remove this file or symbolic link. If the path points to a directory, use
Path.rmdir() instead.

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