# 11.2. `os.path` — manipulation courante des chemins

Code source : Lib/posixpath.py (pour POSIX), Lib/ntpath.py (pour Windows NT), et Lib/macpath.py (pour Macintosh)

Ce module implémente certaines fonctions utiles sur le nom des chemins. Pour lire ou écrire des fichiers, voir `open()`, et pour accéder au système de fichier, voir le module `os`. Les paramètres de chemin d’accès peuvent être passés sous forme de chaînes de caractères ou de chaîne d’octets. Les programmes sont encouragés à représenter les noms de fichiers en tant que chaînes de caractères Unicode. Malheureusement, certains noms de fichiers peuvent ne pas être représentés sous forme de chaînes de caractères sous UNIX, ainsi, les programmes qui doivent prendre en charge les noms de fichiers arbitraires sur UNIX doivent utiliser des chaînes d’octets pour représenter leurs chemins d’accès. Inversement, l’utilisation de chaîne d’octets ne peut pas représenter tous les noms de fichiers sous Windows (dans le codage `mbcs` standard), par conséquent les applications Windows doivent utiliser des chaînes de caractères Unicode pour accéder à tous les fichiers.

Contrairement à une invite de commandes Unix, Python ne fait aucune extension de chemin automatique. Des fonctions telles que `expanduser()` et `expandvars()` peuvent être appelées explicitement lorsqu’une application souhaite une extension de chemin semblable à celui d’une invite de commande (voir aussi le module `glob`).

Voir aussi

Le module `pathlib` offre une représentation objet de haut niveau des chemins.

Note

Toutes ces fonctions n’acceptent que des chaînes d’octets ou des chaînes de caractères en tant que paramètres. Le résultat est un objet du même type si un chemin ou un nom de fichier est renvoyé.

Note

Comme les différents systèmes d’exploitation ont des conventions de noms de chemins différentes, il existe plusieurs versions de ce module dans la bibliothèque standard. Le module `os.path` est toujours le module de chemin adapté au système d’exploitation sur lequel Python tourne, et donc adapté pour les chemins locaux. Cependant, vous pouvez également importer et utiliser les modules individuels si vous voulez manipuler un chemin qui est toujours dans l’un des différents formats. Ils ont tous la même interface :

- `posixpath` pour les chemins de type UNIX

- `ntpath` pour les chemins Windows

- `macpath` pour l’ancienne forme des chemins MacOS

`os.path.``abspath`(path)

  Renvoie une version absolue et normalisée du chemin d’accès path. Sur la plupart des plates-formes, cela équivaut à appeler la fonction `normpath()` comme suit : `normpath(join(os.getcwd(), chemin))``.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``basename`(path)

  Renvoie le nom de base du chemin d’accès path. C’est le second élément de la paire renvoyée en passant path à la fonction `split()`. Notez que le résultat de cette fonction est différent de celui du programme Unix basename ; là où basename pour `'/foo/bar/'` renvoie `'bar'`, la fonction `basename()` renvoie une chaîne vide (`''`).

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``commonpath`(paths)

  Return the longest common sub-path of each pathname in the sequence paths. Raise ValueError if paths contains both absolute and relative pathnames, or if paths is empty. Unlike `commonprefix()`, this returns a valid path.

  Disponibilité Unix, Windows

  Nouveau dans la version 3.5.

  Modifié dans la version 3.6: Accepts a sequence of path-like objects.

`os.path.``commonprefix`(list)

  Return the longest path prefix (taken character-by-character) that is a prefix of all paths in list. If list is empty, return the empty string (`''`).

  Note

  This function may return invalid paths because it works a character at a time. To obtain a valid path, see `commonpath()`.

      >>> os.path.commonprefix(['/usr/lib', '/usr/local/lib'])
      '/usr/l'

      >>> os.path.commonpath(['/usr/lib', '/usr/local/lib'])
      '/usr'

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``dirname`(path)

  Return the directory name of pathname path. This is the first element of the pair returned by passing path to the function `split()`.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``exists`(path)

  Return `True` if path refers to an existing path or an open file descriptor. Returns `False` for broken symbolic links. On some platforms, this function may return `False` if permission is not granted to execute `os.stat()` on the requested file, even if the path physically exists.

  Modifié dans la version 3.3: path can now be an integer: `True` is returned if it is an open file descriptor, `False` otherwise.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``lexists`(path)

  Return `True` if path refers to an existing path. Returns `True` for broken symbolic links. Equivalent to `exists()` on platforms lacking `os.lstat()`.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``expanduser`(path)

  On Unix and Windows, return the argument with an initial component of `~` or `~user` replaced by that user’s home directory.

  On Unix, an initial `~` is replaced by the environment variable `HOME` if it is set; otherwise the current user’s home directory is looked up in the password directory through the built-in module `pwd`. An initial `~user` is looked up directly in the password directory.

  On Windows, `HOME` and `USERPROFILE` will be used if set, otherwise a combination of `HOMEPATH` and `HOMEDRIVE` will be used. An initial `~user` is handled by stripping the last directory component from the created user path derived above.

  If the expansion fails or if the path does not begin with a tilde, the path is returned unchanged.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``expandvars`(path)

  Return the argument with environment variables expanded. Substrings of the form `$name` or `${name}` are replaced by the value of environment variable name. Malformed variable names and references to non-existing variables are left unchanged.

  On Windows, `%name%` expansions are supported in addition to `$name` and `${name}`.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``getatime`(path)

  Return the time of last access of path. The return value is a number giving the number of seconds since the epoch (see the `time` module). Raise `OSError` if the file does not exist or is inaccessible.

  If `os.stat_float_times()` returns `True`, the result is a floating point number.

`os.path.``getmtime`(path)

  Return the time of last modification of path. The return value is a number giving the number of seconds since the epoch (see the `time` module). Raise `OSError` if the file does not exist or is inaccessible.

  If `os.stat_float_times()` returns `True`, the result is a floating point number.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``getctime`(path)

  Return the system’s ctime which, on some systems (like Unix) is the time of the last metadata change, and, on others (like Windows), is the creation time for path. The return value is a number giving the number of seconds since the epoch (see the `time` module). Raise `OSError` if the file does not exist or is inaccessible.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``getsize`(path)

  Return the size, in bytes, of path. Raise `OSError` if the file does not exist or is inaccessible.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``isabs`(path)

  Return `True` if path is an absolute pathname. On Unix, that means it begins with a slash, on Windows that it begins with a (back)slash after chopping off a potential drive letter.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``isfile`(path)

  Return `True` if path is an `existing` regular file. This follows symbolic links, so both `islink()` and `isfile()` can be true for the same path.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``isdir`(path)

  Return `True` if path is an `existing` directory. This follows symbolic links, so both `islink()` and `isdir()` can be true for the same path.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``islink`(path)

  Return `True` if path refers to an `existing` directory entry that is a symbolic link. Always `False` if symbolic links are not supported by the Python runtime.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``ismount`(path)

  Return `True` if pathname path is a mount point: a point in a file system where a different file system has been mounted. On POSIX, the function checks whether path’s parent, `path/..`, is on a different device than path, or whether `path/..` and path point to the same i-node on the same device — this should detect mount points for all Unix and POSIX variants. On Windows, a drive letter root and a share UNC are always mount points, and for any other path `GetVolumePathName` is called to see if it is different from the input path.

  Nouveau dans la version 3.4: Support for detecting non-root mount points on Windows.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``join`(path, *paths)

  Join one or more path components intelligently. The return value is the concatenation of path and any members of *paths with exactly one directory separator (`os.sep`) following each non-empty part except the last, meaning that the result will only end in a separator if the last part is empty. If a component is an absolute path, all previous components are thrown away and joining continues from the absolute path component.

  On Windows, the drive letter is not reset when an absolute path component (e.g., `r'\foo'`) is encountered. If a component contains a drive letter, all previous components are thrown away and the drive letter is reset. Note that since there is a current directory for each drive, `os.path.join("c:", "foo")` represents a path relative to the current directory on drive `C:` (`c:foo`), not `c:\foo`.

  Modifié dans la version 3.6: Accepts a path-like object for path and paths.

`os.path.``normcase`(path)

  Normalize the case of a pathname. On Unix and Mac OS X, this returns the path unchanged; on case-insensitive filesystems, it converts the path to lowercase. On Windows, it also converts forward slashes to backward slashes. Raise a TypeError if the type of path is not `str` or `bytes` (directly or indirectly through the `os.PathLike` interface).

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``normpath`(path)

  Normalize a pathname by collapsing redundant separators and up-level references so that `A//B`, `A/B/`, `A/./B` and `A/foo/../B` all become `A/B`. This string manipulation may change the meaning of a path that contains symbolic links. On Windows, it converts forward slashes to backward slashes. To normalize case, use `normcase()`.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``realpath`(path)

  Return the canonical path of the specified filename, eliminating any symbolic links encountered in the path (if they are supported by the operating system).

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``relpath`(path, start=os.curdir)

  Return a relative filepath to path either from the current directory or from an optional start directory. This is a path computation: the filesystem is not accessed to confirm the existence or nature of path or start.

  start defaults to `os.curdir`.

  Disponibilité : Unix, Windows.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``samefile`(path1, path2)

  Return `True` if both pathname arguments refer to the same file or directory. This is determined by the device number and i-node number and raises an exception if an `os.stat()` call on either pathname fails.

  Disponibilité : Unix, Windows.

  Modifié dans la version 3.2: Prise en charge de Windows.

  Modifié dans la version 3.4: Windows now uses the same implementation as all other platforms.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``sameopenfile`(fp1, fp2)

  Return `True` if the file descriptors fp1 and fp2 refer to the same file.

  Disponibilité : Unix, Windows.

  Modifié dans la version 3.2: Prise en charge de Windows.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``samestat`(stat1, stat2)

  Return `True` if the stat tuples stat1 and stat2 refer to the same file. These structures may have been returned by `os.fstat()`, `os.lstat()`, or `os.stat()`. This function implements the underlying comparison used by `samefile()` and `sameopenfile()`.

  Disponibilité : Unix, Windows.

  Modifié dans la version 3.4: Prise en charge de Windows.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``split`(path)

  Split the pathname path into a pair, `(head, tail)` where tail is the last pathname component and head is everything leading up to that. The tail part will never contain a slash; if path ends in a slash, tail will be empty. If there is no slash in path, head will be empty. If path is empty, both head and tail are empty. Trailing slashes are stripped from head unless it is the root (one or more slashes only). In all cases, `join(head, tail)` returns a path to the same location as path (but the strings may differ). Also see the functions `dirname()` and `basename()`.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``splitdrive`(path)

  Split the pathname path into a pair `(drive, tail)` where drive is either a mount point or the empty string. On systems which do not use drive specifications, drive will always be the empty string. In all cases, `drive + tail` will be the same as path.

  On Windows, splits a pathname into drive/UNC sharepoint and relative path.

  If the path contains a drive letter, drive will contain everything up to and including the colon. e.g. `splitdrive("c:/dir")` returns `("c:", "/dir")`

  If the path contains a UNC path, drive will contain the host name and share, up to but not including the fourth separator. e.g. `splitdrive("//host/computer/dir")` returns `("//host/computer", "/dir")`

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``splitext`(path)

  Split the pathname path into a pair `(root, ext)` such that `root + ext == path`, and ext is empty or begins with a period and contains at most one period. Leading periods on the basename are ignored; `splitext('.cshrc')` returns `('.cshrc', '')`.

  Modifié dans la version 3.6: Accepte un path-like object.

`os.path.``splitunc`(path)

  Obsolète depuis la version 3.1: Use splitdrive instead.

  Split the pathname path into a pair `(unc, rest)` so that unc is the UNC mount point (such as `r'\\host\mount'`), if present, and rest the rest of the path (such as `r'\path\file.ext'`). For paths containing drive letters, unc will always be the empty string.

  Disponibilité : Windows.

`os.path.``supports_unicode_filenames`

  `True` if arbitrary Unicode strings can be used as file names (within limitations imposed by the file system).