:mod:`shutil` --- High-level file operations

============================================

.. module:: shutil

   :synopsis: High-level file operations, including copying.

.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>

.. partly based on the docstrings

.. index::

   single: file; copying

   single: copying files

The :mod:`shutil` module offers a number of high-level operations on files and

collections of files.  In particular, functions are provided  which support file

copying and removal. For operations on individual files, see also the

:mod:`os` module.

.. warning::

   Even the higher-level file copying functions (:func:`copy`, :func:`copy2`)

   can't copy all file metadata.

   On POSIX platforms, this means that file owner and group are lost as well

   as ACLs.  On Mac OS, the resource fork and other metadata are not used.

   This means that resources will be lost and file type and creator codes will

   not be correct. On Windows, file owners, ACLs and alternate data streams

   are not copied.

.. function:: copyfileobj(fsrc, fdst[, length])

   Copy the contents of the file-like object *fsrc* to the file-like object *fdst*.

   The integer *length*, if given, is the buffer size. In particular, a negative

   *length* value means to copy the data without looping over the source data in

   chunks; by default the data is read in chunks to avoid uncontrolled memory

   consumption. Note that if the current file position of the *fsrc* object is not

   0, only the contents from the current file position to the end of the file will

   be copied.

.. function:: copyfile(src, dst)

   Copy the contents (no metadata) of the file named *src* to a file named *dst*.

   *dst* must be the complete target file name; look at :func:`copy` for a copy that

   accepts a target directory path.

   The destination location must be writable; otherwise,  an :exc:`IOError` exception

   will be raised. If *dst* already exists, it will be replaced.   Special files

   such as character or block devices and pipes cannot be copied with this

   function.  *src* and *dst* are path names given as strings.

.. function:: copymode(src, dst)

   Copy the permission bits from *src* to *dst*.  The file contents, owner, and

   group are unaffected.  *src* and *dst* are path names given as strings.

.. function:: copystat(src, dst)

   Copy the permission bits, last access time, last modification time, and flags

   from *src* to *dst*.  The file contents, owner, and group are unaffected.  *src*

   and *dst* are path names given as strings.

.. function:: copy(src, dst)

   Copy the file *src* to the file or directory *dst*.  If *dst* is a directory, a

   file with the same basename as *src*  is created (or overwritten) in the

   directory specified.  Permission bits are copied.  *src* and *dst* are path

   names given as strings.

.. function:: copy2(src, dst)

   Similar to :func:`copy`, but metadata is copied as well -- in fact, this is just

   :func:`copy` followed by :func:`copystat`.  This is similar to the

   Unix command :program:`cp -p`.

.. function:: ignore_patterns(\*patterns)

   This factory function creates a function that can be used as a callable for

   :func:`copytree`\'s *ignore* argument, ignoring files and directories that

   match one of the glob-style *patterns* provided.  See the example below.

   .. versionadded:: 2.6

.. function:: copytree(src, dst[, symlinks=False[, ignore=None]])

   Recursively copy an entire directory tree rooted at *src*.  The destination

   directory, named by *dst*, must not already exist; it will be created as well

   as missing parent directories.  Permissions and times of directories are

   copied with :func:`copystat`, individual files are copied using

   :func:`copy2`.

   If *symlinks* is true, symbolic links in the source tree are represented as

   symbolic links in the new tree; if false or omitted, the contents of the

   linked files are copied to the new tree.

   If *ignore* is given, it must be a callable that will receive as its

   arguments the directory being visited by :func:`copytree`, and a list of its

   contents, as returned by :func:`os.listdir`.  Since :func:`copytree` is

   called recursively, the *ignore* callable will be called once for each

   directory that is copied.  The callable must return a sequence of directory

   and file names relative to the current directory (i.e. a subset of the items

   in its second argument); these names will then be ignored in the copy

   process.  :func:`ignore_patterns` can be used to create such a callable that

   ignores names based on glob-style patterns.

   If exception(s) occur, an :exc:`Error` is raised with a list of reasons.

   The source code for this should be considered an example rather than the

   ultimate tool.

   .. versionchanged:: 2.3

      :exc:`Error` is raised if any exceptions occur during copying, rather than

      printing a message.

   .. versionchanged:: 2.5

      Create intermediate directories needed to create *dst*, rather than raising an

      error. Copy permissions and times of directories using :func:`copystat`.

   .. versionchanged:: 2.6

      Added the *ignore* argument to be able to influence what is being copied. 

.. function:: rmtree(path[, ignore_errors[, onerror]])

   .. index:: single: directory; deleting

   Delete an entire directory tree; *path* must point to a directory (but not a

   symbolic link to a directory).  If *ignore_errors* is true, errors resulting

   from failed removals will be ignored; if false or omitted, such errors are

   handled by calling a handler specified by *onerror* or, if that is omitted,

   they raise an exception.

   If *onerror* is provided, it must be a callable that accepts three

   parameters: *function*, *path*, and *excinfo*. The first parameter,

   *function*, is the function which raised the exception; it will be

   :func:`os.path.islink`, :func:`os.listdir`, :func:`os.remove` or

   :func:`os.rmdir`.  The second parameter, *path*, will be the path name passed

   to *function*.  The third parameter, *excinfo*, will be the exception

   information return by :func:`sys.exc_info`.  Exceptions raised by *onerror*

   will not be caught.

   .. versionchanged:: 2.6

      Explicitly check for *path* being a symbolic link and raise :exc:`OSError`

      in that case.

.. function:: move(src, dst)

   Recursively move a file or directory to another location.

   If the destination is on the current filesystem, then simply use rename.

   Otherwise, copy src to the dst and then remove src.

   .. versionadded:: 2.3

.. exception:: Error

   This exception collects exceptions that raised during a multi-file operation. For

   :func:`copytree`, the exception argument is a list of 3-tuples (*srcname*,

   *dstname*, *exception*).

   .. versionadded:: 2.3

.. _shutil-example:

Example

-------

This example is the implementation of the :func:`copytree` function, described

above, with the docstring omitted.  It demonstrates many of the other functions

provided by this module. ::

   def copytree(src, dst, symlinks=False, ignore=None):

       names = os.listdir(src)

       if ignore is not None:

           ignored_names = ignore(src, names)

       else:

           ignored_names = set()

       os.makedirs(dst)

       errors = []

       for name in names:

           if name in ignored_names:   

               continue

           srcname = os.path.join(src, name)

           dstname = os.path.join(dst, name)

           try:

               if symlinks and os.path.islink(srcname):

                   linkto = os.readlink(srcname)

                   os.symlink(linkto, dstname)

               elif os.path.isdir(srcname):

                   copytree(srcname, dstname, symlinks, ignore)

               else:

                   copy2(srcname, dstname)

               # XXX What about devices, sockets etc.?

           except (IOError, os.error), why:

               errors.append((srcname, dstname, str(why)))

           # catch the Error from the recursive copytree so that we can

           # continue with other files

           except Error, err:

               errors.extend(err.args[0])

       try:

           copystat(src, dst)

       except WindowsError:

           # can't copy file access times on Windows

           pass

       except OSError, why:

           errors.extend((src, dst, str(why)))

       if errors:

           raise Error, errors

Another example that uses the :func:`ignore_patterns` helper::

   from shutil import copytree, ignore_patterns

   copytree(source, destination, ignore=ignore_patterns('*.pyc', 'tmp*'))

This will copy everything except ``.pyc`` files and files or directories whose

name starts with ``tmp``.

Another example that uses the *ignore* argument to add a logging call::

   from shutil import copytree

   import logging

   def _logpath(path, names):

       logging.info('Working in %s' % path)

       return []   # nothing will be ignored

   copytree(source, destination, ignore=_logpath)