6.1.4 Files and Directories

access(path, mode): Use the real uid/gid to test for access to path. Note that most operations will use the effective uid/gid, therefore this routine can be used in a suid/sgid environment to test if the invoking user has the specified access to path. mode should be F_OK to test the existence of path, or it can be the inclusive OR of one or more of R_OK, W_OK, and X_OK to test permissions. Return 1 if access is allowed, 0 if not. See the Unix man page access(2) for more information. Availability: Unix, Windows.

F_OK: Value to pass as the mode parameter of access() to test the existence of path.

R_OK: Value to include in the mode parameter of access() to test the readability of path.

W_OK: Value to include in the mode parameter of access() to test the writability of path.

X_OK: Value to include in the mode parameter of access() to determine if path can be executed.

chdir(path): Change the current working directory to path. Availability: Macintosh, Unix, Windows.

getcwd(): Return a string representing the current working directory. Availability: Macintosh, Unix, Windows.

chroot(path): Change the root directory of the current process to path. Availability: Unix. New in version 2.2.

chmod(path, mode): Change the mode of path to the numeric mode. Availability: Unix, Windows.

chown(path, uid, gid): Change the owner and group id of path to the numeric uid and gid. Availability: Unix.

link(src, dst): Create a hard link pointing to src named dst. Availability: Unix.

listdir(path): Return a list containing the names of the entries in the directory. The list is in arbitrary order. It does not include the special entries '.' and '..' even if they are present in the directory. Availability: Macintosh, Unix, Windows.

lstat(path): Like stat(), but do not follow symbolic links. Availability: Unix.

mkfifo(path[, mode]): Create a FIFO (a named pipe) named path with numeric mode mode. The default mode is 0666 (octal). The current umask value is first masked out from the mode. Availability: Unix.
FIFOs are pipes that can be accessed like regular files. FIFOs exist until they are deleted (for example with os.unlink()). Generally, FIFOs are used as rendezvous between ``client'' and ``server'' type processes: the server opens the FIFO for reading, and the client opens it for writing. Note that mkfifo() doesn't open the FIFO -- it just creates the rendezvous point.

mkdir(path[, mode]): Create a directory named path with numeric mode mode. The default mode is 0777 (octal). On some systems, mode is ignored. Where it is used, the current umask value is first masked out. Availability: Macintosh, Unix, Windows.

makedirs(path[, mode]): Recursive directory creation function. Like mkdir(), but makes all intermediate-level directories needed to contain the leaf directory. Throws an error exception if the leaf directory already exists or cannot be created. The default mode is 0777 (octal). This function does not properly handle UNC paths (only relevant on Windows systems; Universal Naming Convention paths are those that use the `\\host\path' syntax). New in version 1.5.2.

pathconf(path, name): Return system configuration information relevant to a named file. name specifies the configuration value to retrieve; it may be a string which is the name of a defined system value; these names are specified in a number of standards (POSIX.1, Unix95, Unix98, and others). Some platforms define additional names as well. The names known to the host operating system are given in the pathconf_names dictionary. For configuration variables not included in that mapping, passing an integer for name is also accepted. Availability: Unix.
If name is a string and is not known, ValueError is raised. If a specific value for name is not supported by the host system, even if it is included in pathconf_names, an OSError is raised with errno.EINVAL for the error number.

pathconf_names: Dictionary mapping names accepted by pathconf() and fpathconf() to the integer values defined for those names by the host operating system. This can be used to determine the set of names known to the system. Availability: Unix.

readlink(path): Return a string representing the path to which the symbolic link points. The result may be either an absolute or relative pathname; if it is relative, it may be converted to an absolute pathname using os.path.join(os.path.dirname(path), result). Availability: Unix.

remove(path): Remove the file path. If path is a directory, OSError is raised; see rmdir() below to remove a directory. This is identical to the unlink() function documented below. On Windows, attempting to remove a file that is in use causes an exception to be raised; on Unix, the directory entry is removed but the storage allocated to the file is not made available until the original file is no longer in use. Availability: Macintosh, Unix, Windows.

removedirs(path): Recursive directory removal function. Works like rmdir() except that, if the leaf directory is successfully removed, directories corresponding to rightmost path segments will be pruned way until either the whole path is consumed or an error is raised (which is ignored, because it generally means that a parent directory is not empty). Throws an error exception if the leaf directory could not be successfully removed. New in version 1.5.2.

rename(src, dst): Rename the file or directory src to dst. If dst is a directory, OSError will be raised. On Unix, if dst exists and is a file, it will be removed silently if the user has permission. The operation may fail on some Unix flavors if src and dst are on different filesystems. If successful, the renaming will be an atomic operation (this is a POSIX requirement). On Windows, if dst already exists, OSError will be raised even if it is a file; there may be no way to implement an atomic rename when dst names an existing file. Availability: Macintosh, Unix, Windows.

renames(old, new): Recursive directory or file renaming function. Works like rename(), except creation of any intermediate directories needed to make the new pathname good is attempted first. After the rename, directories corresponding to rightmost path segments of the old name will be pruned away using removedirs().
Note: this function can fail with the new directory structure made if you lack permissions needed to remove the leaf directory or file. New in version 1.5.2.

rmdir(path): Remove the directory path. Availability: Macintosh, Unix, Windows.

stat(path)

Perform a stat() system call on the given path. The return value is an object whose attributes correspond to the members of the stat structure, namely: st_mode (protection bits), st_ino (inode number), st_dev (device), st_nlink (number of hard links), st_uid (user ID of owner), st_gid (group ID of owner), st_size (size of file, in bytes), st_atime (time of most recent access), st_mtime (time of most recent content modification), st_ctime (time of most recent content modification or metadata change).

On some Unix systems (such as Linux), the following attributes may also be available: st_blocks (number of blocks allocated for file), st_blksize (filesystem blocksize), st_rdev (type of device if an inode device).

On Mac OS systems, the following attributes may also be available: st_rsize, st_creator, st_type.

On RISCOS systems, the following attributes are also available: st_ftype (file type), st_attrs (attributes), st_obtype (object type).

For backward compatibility, the return value of stat() is also accessible as a tuple of at least 10 integers giving the most important (and portable) members of the stat structure, in the order st_mode, st_ino, st_dev, st_nlink, st_uid, st_gid, st_size, st_atime, st_mtime, st_ctime. More items may be added at the end by some implementations. Note that on the Mac OS, the time values are floating point values, like all time values on the Mac OS. The standard module stat defines functions and constants that are useful for extracting information from a stat structure. (On Windows, some items are filled with dummy values.) Availability: Macintosh, Unix, Windows.

Changed in version 2.2: Added access to values as attributes of the returned object.

statvfs(path)

Perform a statvfs() system call on the given path. The return value is an object whose attributes describe the filesystem on the given path, and correspond to the members of the statvfs structure, namely: f_frsize, f_blocks, f_bfree, f_bavail, f_files, f_ffree, f_favail, f_flag, f_namemax. Availability: Unix.

For backward compatibility, the return value is also accessible as a tuple whose values correspond to the attributes, in the order given above. The standard module statvfs defines constants that are useful for extracting information from a statvfs structure when accessing it as a sequence; this remains useful when writing code that needs to work with versions of Python that don't support accessing the fields as attributes.

Changed in version 2.2: Added access to values as attributes of the returned object.

symlink(src, dst): Create a symbolic link pointing to src named dst. Availability: Unix.

tempnam([dir[, prefix]]): Return a unique path name that is reasonable for creating a temporary file. This will be an absolute path that names a potential directory entry in the directory dir or a common location for temporary files if dir is omitted or None. If given and not None, prefix is used to provide a short prefix to the filename. Applications are responsible for properly creating and managing files created using paths returned by tempnam(); no automatic cleanup is provided. On Unix, the environment variable TMPDIR overrides dir, while on Windows the TMP is used. The specific behavior of this function depends on the C library implementation; some aspects are underspecified in system documentation. Warning: Use of tempnam() is vulnerable to symlink attacks; consider using tmpfile() instead. Availability: Unix, Windows.

tmpnam(): Return a unique path name that is reasonable for creating a temporary file. This will be an absolute path that names a potential directory entry in a common location for temporary files. Applications are responsible for properly creating and managing files created using paths returned by tmpnam(); no automatic cleanup is provided. Warning: Use of tmpnam() is vulnerable to symlink attacks; consider using tmpfile() instead. Availability: Unix, Windows.

TMP_MAX: The maximum number of unique names that tmpnam() will generate before reusing names.

unlink(path): Remove the file path. This is the same function as remove(); the unlink() name is its traditional Unix name. Availability: Macintosh, Unix, Windows.

utime(path, times): Set the access and modified times of the file specified by path. If times is None, then the file's access and modified times are set to the current time. Otherwise, times must be a 2-tuple of numbers, of the form (atime, mtime) which is used to set the access and modified times, respectively. Changed in version 2.0: Added support for None for times. Availability: Macintosh, Unix, Windows.

See About this document... for information on suggesting changes.