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Table of Contents generated with DocToc

18.1 bz2

The bz2 module is used to read and write data compressed according to the bzip2 compression algorithm.

  • BZ2File(filename [, mode [, buffering [, compresslevel]]]) Opens a .bz2 file, filename, and returns a file-like object.
  • BZ2Compressor([compresslevel]) Creates a compressor object that can be used to sequentially compress a sequence of data blocks. An instance, c, of BZ2Compressor has the following methods:
    • c.compress(data) Feeds new string data to the compressor object, c. Returns a string of compressed data if possible.
  • BZ2Decompressor() Creates a decompressor object. An instance, d, of BZ2Decompressor supports just one method:
    • d.decompress(data) Given a chunk of compressed data in the string data, this method returns uncompressed data.
  • compress(data [, compresslevel]) Returns a compressed version of the data supplied in the string data.
  • decompress(data) Returns a string containing the decompressed data in the string data.

18.2 filecmp

The filecmp module provides the following functions, which can be used to compare files and directories:

  • cmp(file1, file2 [, shallow]) Compares the files file1 and file2 and returns True if they’re equal, False if not.
  • dircmp(dir1, dir2 [, ignore[, hide]]) Creates a directory comparison object that can be used to perform various comparison operations on the directories dir1 and dir2. A directory object, d has following methods and attribues:
    • d.report() Compares directories dir1 and dir2 and prints a report to sys.stdout.
    • d.left_list Lists the files and subdirectories in dir1.
    • d.common_files   Lists the files that are common to dir1 and dir2.
    • d.diff_files   Lists the files with different contents in dir1 and dir2.

18.3 fnmatch

The fnmatch module provides support for matching filenames using UNIX shell-style wildcard characters. This module only performs filename matching, whereas the glob module can be used to actually obtain file listings.

fnmatch(filename, pattern) Returns True or False depending on whether filename matches pattern.

filter(names, pattern) Applies the fnmatch() function to all of the names in the sequence names and returns a list of all names that match pattern.

18.4 glob

The glob module returns all filenames in a directory that match a pattern specified using the rules of the UNIX shell (as described in the fnmatch module).  

glob(pattern) Returns a list of pathnames that match pattern.

18.5 gzip

The gzip module provides a class, GzipFile, that can be used to read and write files compatible with the GNU gzip program. GzipFile objects work like ordinary files except that data is automatically compressed or decompressed.  

GzipFile([filename [, mode [, compresslevel [, fileobj]]]]) Opens a GzipFile.

18.6 shutil

The shutil module is used to perform high-level file operations such as copying, removing, and renaming. The functions in this module should only be used for proper files and directories. In particular, they do not work for special kinds of files on the file system such as named pipes, block devices, etc.

  • copy(src,dst) Copies the file src to the file or directory dst, retaining file permissions. src and dst are strings.
  • move(src, dst) Moves a file or directory src to dst.
  • rmtree(path [, ignore_errors [, onerror]]) Deletes an entire directory tree.

18.7 tarfile

The tarfile module is used to manipulate tar archive files. Using this module, it is possible to read and write tar files, with or without compression.

open([name [, mode [, fileobj [, bufsize]]]]) Creates a new TarFile object with the pathname name.

A TarFile instance, t, returned by open() supports the following methods and attributes:  

  • t.add(name [, arcname [, recursive]]) Adds a new file to the tar archive.
  • t.extract(member [, path]) Extracts a member from the archive, saving it to the current directory.
  • t.getmember(name) Looks up archive member name and returns a TarInfo object containing information about it.
  • t.gettarinfo([name [, arcname [, fileobj]]]) Returns a TarInfo object corresponding to a file, name, on the file system or an open file object, fi`leobj. arcname is an alternative name for the object in the archive.
  • t.list([verbose]) Lists the contents of the archive to sys.stdout.
  • t.next() A method used for iterating over the members of an archive.

18.8 tempfile

The tempfile module is used to generate temporary filenames and files.  

  • mkdtemp([suffix [,prefix [, dir]]])   Creates a temporary directory accessible only by the owner of the calling process and returns its absolute pathname. -TemporaryFile([mode [, bufsize [, suffix [,prefix [, dir]]]]])   Creates a temporary file using mkstemp() and returns a file-like object that supports the same methods as an ordinary file object.
  • NamedTemporaryFile([mode [, bufsize [, suffix [,prefix [, dir [, delete ]]]]]])  Creates a temporary file just like TemporaryFile() but makes sure the filename is visible on the file system.

18.9 zipfile

The zipfile module is used to manipulate files encoded in the popular zip format (originally known as PKZIP, although now supported by a wide variety of programs).

  • ZipFile(filename [, mode [, compression [,allowZip64]]])   Opens a zip file, filename, and returns a ZipFile instance.
  • ZipInfo([filename [, date_time]])   Manually creates a new ZipInfo instance, used to contain information about an archive member.

An instance, z, of ZipFile or PyZipFile supports the following methods and attributes:

  • z.extract(name [, path [, pwd ]])   Extracts a file from the archive and places it in the current working directory.
  • z.open(name [, mode [, pwd]])   Opens an archive member named name and returns a file-like object for reading the contents.
  • z.read(name [,pwd])   Reads archive contents for member name and returns the data as a string.
  • z.write(filename[, arcname[, compress_type]])   Writes filename to the archive with the archive name arcname.

18.10 zlib

The zlib module supports data compression by providing access to the zlib library.

  • compress(string [, level])   Compresses the data in string, where level is an integer from 1 to 9 controlling the level of compression.
  • decompress(string [, wbits [, buffsize]])   Decompresses the data in string. wbits controls the size of the window buffer, and buffsize is the initial size of the output buffer. Raises error if an error occurs.

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