Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1 | :mod:`os.path` --- Common pathname manipulations |
| 2 | ================================================ |
| 3 | |
| 4 | .. module:: os.path |
| 5 | :synopsis: Operations on pathnames. |
| 6 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 7 | .. index:: single: path; operations |
| 8 | |
| 9 | This module implements some useful functions on pathnames. To read or |
| 10 | write files see :func:`open`, and for accessing the filesystem see the |
Martin v. Löwis | 651423c | 2008-10-07 07:03:04 +0000 | [diff] [blame] | 11 | :mod:`os` module. The path parameters can be passed as either strings, |
| 12 | or bytes. Applications are encouraged to represent file names as |
| 13 | (Unicode) character strings. Unfortunately, some file names may not be |
| 14 | representable as strings on Unix, so applications that need to support |
| 15 | arbitrary file names on Unix should use bytes objects to represent |
| 16 | path names. Vice versa, using bytes objects cannot represent all file |
| 17 | names on Windows (in the standard ``mbcs`` encoding), hence Windows |
| 18 | applications should use string objects to access all files. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 19 | |
R David Murray | a4e700c | 2013-01-06 16:13:10 -0500 | [diff] [blame] | 20 | Unlike a unix shell, Python does not do any *automatic* path expansions. |
| 21 | Functions such as :func:`expanduser` and :func:`expandvars` can be invoked |
| 22 | explicitly when an application desires shell-like path expansion. (See also |
| 23 | the :mod:`glob` module.) |
| 24 | |
Georg Brandl | 76e5538 | 2008-10-08 16:34:57 +0000 | [diff] [blame] | 25 | .. note:: |
| 26 | |
| 27 | All of these functions accept either only bytes or only string objects as |
| 28 | their parameters. The result is an object of the same type, if a path or |
| 29 | file name is returned. |
| 30 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 31 | |
Benjamin Peterson | d23f822 | 2009-04-05 19:13:16 +0000 | [diff] [blame] | 32 | .. note:: |
| 33 | |
| 34 | Since different operating systems have different path name conventions, there |
| 35 | are several versions of this module in the standard library. The |
| 36 | :mod:`os.path` module is always the path module suitable for the operating |
| 37 | system Python is running on, and therefore usable for local paths. However, |
| 38 | you can also import and use the individual modules if you want to manipulate |
| 39 | a path that is *always* in one of the different formats. They all have the |
| 40 | same interface: |
| 41 | |
| 42 | * :mod:`posixpath` for UNIX-style paths |
| 43 | * :mod:`ntpath` for Windows paths |
| 44 | * :mod:`macpath` for old-style MacOS paths |
| 45 | * :mod:`os2emxpath` for OS/2 EMX paths |
| 46 | |
| 47 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 48 | .. function:: abspath(path) |
| 49 | |
| 50 | Return a normalized absolutized version of the pathname *path*. On most |
Chris Jerdonek | 0b502ff | 2012-11-25 20:38:01 -0800 | [diff] [blame] | 51 | platforms, this is equivalent to calling the function :func:`normpath` as |
| 52 | follows: ``normpath(join(os.getcwd(), path))``. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 53 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 54 | |
| 55 | .. function:: basename(path) |
| 56 | |
Chris Jerdonek | 0b502ff | 2012-11-25 20:38:01 -0800 | [diff] [blame] | 57 | Return the base name of pathname *path*. This is the second element of the |
| 58 | pair returned by passing *path* to the function :func:`split`. Note that |
| 59 | the result of this function is different |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 60 | from the Unix :program:`basename` program; where :program:`basename` for |
| 61 | ``'/foo/bar/'`` returns ``'bar'``, the :func:`basename` function returns an |
| 62 | empty string (``''``). |
| 63 | |
| 64 | |
| 65 | .. function:: commonprefix(list) |
| 66 | |
| 67 | Return the longest path prefix (taken character-by-character) that is a prefix |
| 68 | of all paths in *list*. If *list* is empty, return the empty string (``''``). |
| 69 | Note that this may return invalid paths because it works a character at a time. |
| 70 | |
| 71 | |
| 72 | .. function:: dirname(path) |
| 73 | |
Chris Jerdonek | 0b502ff | 2012-11-25 20:38:01 -0800 | [diff] [blame] | 74 | Return the directory name of pathname *path*. This is the first element of |
| 75 | the pair returned by passing *path* to the function :func:`split`. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 76 | |
| 77 | |
| 78 | .. function:: exists(path) |
| 79 | |
Richard Oudkerk | 2240ac1 | 2012-07-06 12:05:32 +0100 | [diff] [blame] | 80 | Return ``True`` if *path* refers to an existing path or an open |
| 81 | file descriptor. Returns ``False`` for broken symbolic links. On |
| 82 | some platforms, this function may return ``False`` if permission is |
| 83 | not granted to execute :func:`os.stat` on the requested file, even |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 84 | if the *path* physically exists. |
| 85 | |
Richard Oudkerk | 2240ac1 | 2012-07-06 12:05:32 +0100 | [diff] [blame] | 86 | .. versionchanged:: 3.3 |
| 87 | *path* can now be an integer: ``True`` is returned if it is an |
| 88 | open file descriptor, ``False`` otherwise. |
| 89 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 90 | |
| 91 | .. function:: lexists(path) |
| 92 | |
| 93 | Return ``True`` if *path* refers to an existing path. Returns ``True`` for |
| 94 | broken symbolic links. Equivalent to :func:`exists` on platforms lacking |
| 95 | :func:`os.lstat`. |
| 96 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 97 | |
| 98 | .. function:: expanduser(path) |
| 99 | |
| 100 | On Unix and Windows, return the argument with an initial component of ``~`` or |
| 101 | ``~user`` replaced by that *user*'s home directory. |
| 102 | |
| 103 | .. index:: module: pwd |
| 104 | |
| 105 | On Unix, an initial ``~`` is replaced by the environment variable :envvar:`HOME` |
| 106 | if it is set; otherwise the current user's home directory is looked up in the |
| 107 | password directory through the built-in module :mod:`pwd`. An initial ``~user`` |
| 108 | is looked up directly in the password directory. |
| 109 | |
| 110 | On Windows, :envvar:`HOME` and :envvar:`USERPROFILE` will be used if set, |
| 111 | otherwise a combination of :envvar:`HOMEPATH` and :envvar:`HOMEDRIVE` will be |
| 112 | used. An initial ``~user`` is handled by stripping the last directory component |
| 113 | from the created user path derived above. |
| 114 | |
| 115 | If the expansion fails or if the path does not begin with a tilde, the path is |
| 116 | returned unchanged. |
| 117 | |
| 118 | |
| 119 | .. function:: expandvars(path) |
| 120 | |
| 121 | Return the argument with environment variables expanded. Substrings of the form |
| 122 | ``$name`` or ``${name}`` are replaced by the value of environment variable |
| 123 | *name*. Malformed variable names and references to non-existing variables are |
| 124 | left unchanged. |
| 125 | |
| 126 | On Windows, ``%name%`` expansions are supported in addition to ``$name`` and |
| 127 | ``${name}``. |
| 128 | |
| 129 | |
| 130 | .. function:: getatime(path) |
| 131 | |
| 132 | Return the time of last access of *path*. The return value is a number giving |
| 133 | the number of seconds since the epoch (see the :mod:`time` module). Raise |
Andrew Svetlov | 618c2e1 | 2012-12-15 22:59:24 +0200 | [diff] [blame] | 134 | :exc:`OSError` if the file does not exist or is inaccessible. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 135 | |
Georg Brandl | 55ac8f0 | 2007-09-01 13:51:09 +0000 | [diff] [blame] | 136 | If :func:`os.stat_float_times` returns True, the result is a floating point |
| 137 | number. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 138 | |
| 139 | |
| 140 | .. function:: getmtime(path) |
| 141 | |
| 142 | Return the time of last modification of *path*. The return value is a number |
| 143 | giving the number of seconds since the epoch (see the :mod:`time` module). |
Andrew Svetlov | 618c2e1 | 2012-12-15 22:59:24 +0200 | [diff] [blame] | 144 | Raise :exc:`OSError` if the file does not exist or is inaccessible. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 145 | |
Georg Brandl | 55ac8f0 | 2007-09-01 13:51:09 +0000 | [diff] [blame] | 146 | If :func:`os.stat_float_times` returns True, the result is a floating point |
| 147 | number. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 148 | |
| 149 | |
| 150 | .. function:: getctime(path) |
| 151 | |
| 152 | Return the system's ctime which, on some systems (like Unix) is the time of the |
| 153 | last change, and, on others (like Windows), is the creation time for *path*. |
| 154 | The return value is a number giving the number of seconds since the epoch (see |
Andrew Svetlov | 618c2e1 | 2012-12-15 22:59:24 +0200 | [diff] [blame] | 155 | the :mod:`time` module). Raise :exc:`OSError` if the file does not exist or |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 156 | is inaccessible. |
| 157 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 158 | |
| 159 | .. function:: getsize(path) |
| 160 | |
Andrew Svetlov | 618c2e1 | 2012-12-15 22:59:24 +0200 | [diff] [blame] | 161 | Return the size, in bytes, of *path*. Raise :exc:`OSError` if the file does |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 162 | not exist or is inaccessible. |
| 163 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 164 | |
| 165 | .. function:: isabs(path) |
| 166 | |
Christian Heimes | af98da1 | 2008-01-27 15:18:18 +0000 | [diff] [blame] | 167 | Return ``True`` if *path* is an absolute pathname. On Unix, that means it |
| 168 | begins with a slash, on Windows that it begins with a (back)slash after chopping |
| 169 | off a potential drive letter. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 170 | |
| 171 | |
| 172 | .. function:: isfile(path) |
| 173 | |
| 174 | Return ``True`` if *path* is an existing regular file. This follows symbolic |
| 175 | links, so both :func:`islink` and :func:`isfile` can be true for the same path. |
| 176 | |
| 177 | |
| 178 | .. function:: isdir(path) |
| 179 | |
| 180 | Return ``True`` if *path* is an existing directory. This follows symbolic |
| 181 | links, so both :func:`islink` and :func:`isdir` can be true for the same path. |
| 182 | |
| 183 | |
| 184 | .. function:: islink(path) |
| 185 | |
| 186 | Return ``True`` if *path* refers to a directory entry that is a symbolic link. |
| 187 | Always ``False`` if symbolic links are not supported. |
| 188 | |
| 189 | |
| 190 | .. function:: ismount(path) |
| 191 | |
| 192 | Return ``True`` if pathname *path* is a :dfn:`mount point`: a point in a file |
| 193 | system where a different file system has been mounted. The function checks |
| 194 | whether *path*'s parent, :file:`path/..`, is on a different device than *path*, |
| 195 | or whether :file:`path/..` and *path* point to the same i-node on the same |
| 196 | device --- this should detect mount points for all Unix and POSIX variants. |
| 197 | |
| 198 | |
| 199 | .. function:: join(path1[, path2[, ...]]) |
| 200 | |
| 201 | Join one or more path components intelligently. If any component is an absolute |
| 202 | path, all previous components (on Windows, including the previous drive letter, |
| 203 | if there was one) are thrown away, and joining continues. The return value is |
| 204 | the concatenation of *path1*, and optionally *path2*, etc., with exactly one |
R David Murray | 24eb4bc | 2011-06-23 21:26:13 -0400 | [diff] [blame] | 205 | directory separator (``os.sep``) following each non-empty part except the last. |
| 206 | (This means that an empty last part will result in a path that ends with a |
| 207 | separator.) Note that on Windows, since there is a current directory for |
| 208 | each drive, ``os.path.join("c:", "foo")`` represents a path relative to the |
| 209 | current directory on drive :file:`C:` (:file:`c:foo`), not :file:`c:\\foo`. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 210 | |
| 211 | |
| 212 | .. function:: normcase(path) |
| 213 | |
Benjamin Peterson | d23f822 | 2009-04-05 19:13:16 +0000 | [diff] [blame] | 214 | Normalize the case of a pathname. On Unix and Mac OS X, this returns the |
| 215 | path unchanged; on case-insensitive filesystems, it converts the path to |
| 216 | lowercase. On Windows, it also converts forward slashes to backward slashes. |
Ezio Melotti | 5a3ef5b | 2010-06-25 10:56:11 +0000 | [diff] [blame] | 217 | Raise a TypeError if the type of *path* is not ``str`` or ``bytes``. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 218 | |
| 219 | |
| 220 | .. function:: normpath(path) |
| 221 | |
Terry Jan Reedy | ec6e132 | 2013-03-17 15:21:26 -0400 | [diff] [blame] | 222 | Normalize a pathname by collapsing redundant separators and up-level |
| 223 | references so that ``A//B``, ``A/B/``, ``A/./B`` and ``A/foo/../B`` all |
| 224 | become ``A/B``. This string manipulation may change the meaning of a path |
| 225 | that contains symbolic links. On Windows, it converts forward slashes to |
Terry Jan Reedy | f346041 | 2013-03-17 15:28:10 -0400 | [diff] [blame] | 226 | backward slashes. To normalize case, use :func:`normcase`. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 227 | |
| 228 | |
| 229 | .. function:: realpath(path) |
| 230 | |
| 231 | Return the canonical path of the specified filename, eliminating any symbolic |
| 232 | links encountered in the path (if they are supported by the operating system). |
| 233 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 234 | |
Georg Brandl | 1824415 | 2009-09-02 20:34:52 +0000 | [diff] [blame] | 235 | .. function:: relpath(path, start=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 236 | |
| 237 | Return a relative filepath to *path* either from the current directory or from |
| 238 | an optional *start* point. |
| 239 | |
Benjamin Peterson | f650e46 | 2010-05-06 23:03:05 +0000 | [diff] [blame] | 240 | *start* defaults to :attr:`os.curdir`. |
| 241 | |
Antoine Pitrou | f10f162 | 2010-12-12 20:17:29 +0000 | [diff] [blame] | 242 | Availability: Unix, Windows. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 243 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 244 | |
| 245 | .. function:: samefile(path1, path2) |
| 246 | |
Brian Curtin | d40e6f7 | 2010-07-08 21:39:08 +0000 | [diff] [blame] | 247 | Return ``True`` if both pathname arguments refer to the same file or directory. |
| 248 | On Unix, this is determined by the device number and i-node number and raises an |
| 249 | exception if a :func:`os.stat` call on either pathname fails. |
Benjamin Peterson | f650e46 | 2010-05-06 23:03:05 +0000 | [diff] [blame] | 250 | |
Brian Curtin | d40e6f7 | 2010-07-08 21:39:08 +0000 | [diff] [blame] | 251 | On Windows, two files are the same if they resolve to the same final path |
Brian Curtin | c739569 | 2010-07-09 15:15:09 +0000 | [diff] [blame] | 252 | name using the Windows API call GetFinalPathNameByHandle. This function |
Brian Curtin | d40e6f7 | 2010-07-08 21:39:08 +0000 | [diff] [blame] | 253 | raises an exception if handles cannot be obtained to either file. |
| 254 | |
Antoine Pitrou | f10f162 | 2010-12-12 20:17:29 +0000 | [diff] [blame] | 255 | Availability: Unix, Windows. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 256 | |
Georg Brandl | b382337 | 2010-07-10 08:58:37 +0000 | [diff] [blame] | 257 | .. versionchanged:: 3.2 |
| 258 | Added Windows support. |
Brian Curtin | c739569 | 2010-07-09 15:15:09 +0000 | [diff] [blame] | 259 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 260 | |
| 261 | .. function:: sameopenfile(fp1, fp2) |
| 262 | |
| 263 | Return ``True`` if the file descriptors *fp1* and *fp2* refer to the same file. |
Benjamin Peterson | f650e46 | 2010-05-06 23:03:05 +0000 | [diff] [blame] | 264 | |
Brian Curtin | 6285774 | 2010-09-06 17:07:27 +0000 | [diff] [blame] | 265 | Availability: Unix, Windows. |
| 266 | |
Georg Brandl | 61063cc | 2012-06-24 22:48:30 +0200 | [diff] [blame] | 267 | .. versionchanged:: 3.2 |
| 268 | Added Windows support. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 269 | |
| 270 | |
| 271 | .. function:: samestat(stat1, stat2) |
| 272 | |
| 273 | Return ``True`` if the stat tuples *stat1* and *stat2* refer to the same file. |
| 274 | These structures may have been returned by :func:`fstat`, :func:`lstat`, or |
| 275 | :func:`stat`. This function implements the underlying comparison used by |
Benjamin Peterson | f650e46 | 2010-05-06 23:03:05 +0000 | [diff] [blame] | 276 | :func:`samefile` and :func:`sameopenfile`. |
| 277 | |
| 278 | Availability: Unix. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 279 | |
| 280 | |
| 281 | .. function:: split(path) |
| 282 | |
Georg Brandl | 539c165 | 2010-10-14 06:46:08 +0000 | [diff] [blame] | 283 | Split the pathname *path* into a pair, ``(head, tail)`` where *tail* is the |
| 284 | last pathname component and *head* is everything leading up to that. The |
| 285 | *tail* part will never contain a slash; if *path* ends in a slash, *tail* |
| 286 | will be empty. If there is no slash in *path*, *head* will be empty. If |
| 287 | *path* is empty, both *head* and *tail* are empty. Trailing slashes are |
| 288 | stripped from *head* unless it is the root (one or more slashes only). In |
| 289 | all cases, ``join(head, tail)`` returns a path to the same location as *path* |
Chris Jerdonek | 0b502ff | 2012-11-25 20:38:01 -0800 | [diff] [blame] | 290 | (but the strings may differ). Also see the functions :func:`dirname` and |
| 291 | :func:`basename`. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 292 | |
| 293 | |
| 294 | .. function:: splitdrive(path) |
| 295 | |
| 296 | Split the pathname *path* into a pair ``(drive, tail)`` where *drive* is either |
Mark Hammond | 5a607a3 | 2009-05-06 08:04:54 +0000 | [diff] [blame] | 297 | a mount point or the empty string. On systems which do not use drive |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 298 | specifications, *drive* will always be the empty string. In all cases, ``drive |
| 299 | + tail`` will be the same as *path*. |
| 300 | |
Mark Hammond | 5a607a3 | 2009-05-06 08:04:54 +0000 | [diff] [blame] | 301 | On Windows, splits a pathname into drive/UNC sharepoint and relative path. |
| 302 | |
| 303 | If the path contains a drive letter, drive will contain everything |
| 304 | up to and including the colon. |
| 305 | e.g. ``splitdrive("c:/dir")`` returns ``("c:", "/dir")`` |
| 306 | |
| 307 | If the path contains a UNC path, drive will contain the host name |
| 308 | and share, up to but not including the fourth separator. |
| 309 | e.g. ``splitdrive("//host/computer/dir")`` returns ``("//host/computer", "/dir")`` |
| 310 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 311 | |
| 312 | .. function:: splitext(path) |
| 313 | |
| 314 | Split the pathname *path* into a pair ``(root, ext)`` such that ``root + ext == |
| 315 | path``, and *ext* is empty or begins with a period and contains at most one |
| 316 | period. Leading periods on the basename are ignored; ``splitext('.cshrc')`` |
| 317 | returns ``('.cshrc', '')``. |
| 318 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 319 | |
| 320 | .. function:: splitunc(path) |
| 321 | |
Mark Hammond | 5a607a3 | 2009-05-06 08:04:54 +0000 | [diff] [blame] | 322 | .. deprecated:: 3.1 |
| 323 | Use *splitdrive* instead. |
| 324 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 325 | Split the pathname *path* into a pair ``(unc, rest)`` so that *unc* is the UNC |
| 326 | mount point (such as ``r'\\host\mount'``), if present, and *rest* the rest of |
| 327 | the path (such as ``r'\path\file.ext'``). For paths containing drive letters, |
Benjamin Peterson | f650e46 | 2010-05-06 23:03:05 +0000 | [diff] [blame] | 328 | *unc* will always be the empty string. |
| 329 | |
| 330 | Availability: Windows. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 331 | |
| 332 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 333 | .. data:: supports_unicode_filenames |
| 334 | |
| 335 | True if arbitrary Unicode strings can be used as file names (within limitations |
Victor Stinner | b55e498 | 2010-09-11 00:22:12 +0000 | [diff] [blame] | 336 | imposed by the file system). |