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-rw-r--r--doc/source/library/apt.cache.rst83
-rw-r--r--doc/source/library/apt.cdrom.rst7
-rw-r--r--doc/source/library/apt.debfile.rst39
-rw-r--r--doc/source/library/apt.package.rst122
-rw-r--r--doc/source/library/apt.progress.base.rst335
-rw-r--r--doc/source/library/apt.progress.text.rst21
-rw-r--r--doc/source/library/apt_inst.rst323
-rw-r--r--doc/source/library/apt_pkg.rst2904
-rw-r--r--doc/source/library/aptsources.distinfo.rst11
-rw-r--r--doc/source/library/aptsources.distro.rst11
-rw-r--r--doc/source/library/aptsources.sourceslist.rst11
-rw-r--r--doc/source/library/index.rst35
12 files changed, 3902 insertions, 0 deletions
diff --git a/doc/source/library/apt.cache.rst b/doc/source/library/apt.cache.rst
new file mode 100644
index 0000000..f85deb2
--- /dev/null
+++ b/doc/source/library/apt.cache.rst
@@ -0,0 +1,83 @@
+:mod:`apt.cache` --- The Cache class
+=====================================
+.. automodule:: apt.cache
+
+The Cache class
+---------------
+
+.. autoclass:: Cache
+ :members:
+ :undoc-members:
+
+ .. describe:: cache[pkgname]
+
+ Return a :class:`Package()` for the package with the name *pkgname*.
+
+Example
+^^^^^^^
+
+The following example shows how to load the cache, update it, and upgrade
+all the packages on the system::
+
+ import apt
+ import apt.progress
+
+ # First of all, open the cache
+ cache = apt.Cache()
+ # Now, lets update the package list
+ cache.update()
+ # We need to re-open the cache because it needs to read the package list
+ cache.open(None)
+ # Now we can do the same as 'apt-get upgrade' does
+ cache.upgrade()
+ # or we can play 'apt-get dist-upgrade'
+ cache.upgrade(True)
+ # Q: Why does nothing happen?
+ # A: You forgot to call commit()!
+ cache.commit(apt.progress.TextFetchProgress(),
+ apt.progress.InstallProgress())
+
+
+
+Working with Filters
+--------------------
+.. autoclass:: Filter
+ :members:
+ :inherited-members:
+ :undoc-members:
+
+.. autoclass:: MarkedChangesFilter
+ :members:
+ :inherited-members:
+ :undoc-members:
+
+.. autoclass:: FilteredCache
+ :members:
+ :inherited-members:
+ :undoc-members:
+
+
+Example
+^^^^^^^
+
+This is an example for a filtered cache, which only allows access to the
+packages whose state has been changed, eg. packages marked for installation::
+
+ >>> from apt.cache import FilteredCache, Cache, MarkedChangesFilter
+ >>> cache = apt.Cache()
+ >>> changed = apt.FilteredCache(cache)
+ >>> changed.set_filter(MarkedChangesFilter())
+ >>> print(len(changed) == len(cache.get_changes())) # Both need to have same length
+ True
+
+The ProblemResolver class
+--------------------------
+
+.. autoclass:: ProblemResolver
+ :members:
+
+Exceptions
+----------
+.. autoexception:: FetchCancelledException
+.. autoexception:: FetchFailedException
+.. autoexception:: LockFailedException
diff --git a/doc/source/library/apt.cdrom.rst b/doc/source/library/apt.cdrom.rst
new file mode 100644
index 0000000..56381f1
--- /dev/null
+++ b/doc/source/library/apt.cdrom.rst
@@ -0,0 +1,7 @@
+:mod:`apt.cdrom` - Functionality like in apt-cdrom
+====================================================
+.. automodule:: apt.cdrom
+ :members:
+
+
+
diff --git a/doc/source/library/apt.debfile.rst b/doc/source/library/apt.debfile.rst
new file mode 100644
index 0000000..7133b5a
--- /dev/null
+++ b/doc/source/library/apt.debfile.rst
@@ -0,0 +1,39 @@
+:mod:`apt.debfile` --- Classes related to debian package files
+==============================================================
+The :mod:`apt.debfile` provides classes to work with locally available
+debian packages, or source packages.
+
+.. module:: apt.debfile
+
+Binary packages
+----------------
+.. autoclass:: DebPackage
+ :members:
+ :inherited-members:
+ :undoc-members:
+
+ The :class:`DebPackage` class is a class for working with '.deb' files,
+ also known as Debian packages.
+
+ It provides methods and attributes to get a list of the files in the
+ package, to install the package and much more.
+
+ If you specify *cache* it has to point to an :class:`apt.cache.Cache()`
+ object.
+
+ .. versionchanged:: 0.7.9
+ Introduce all new methods (everything except for :meth:`open()` and
+ :attr:`filelist`)
+
+
+Source packages
+----------------
+.. autoclass:: DscSrcPackage
+ :members:
+ :inherited-members:
+ :undoc-members:
+
+ Provide functionality to work with locally available source packages,
+ especially with their '.dsc' file.
+
+ .. versionadded:: 0.7.9
diff --git a/doc/source/library/apt.package.rst b/doc/source/library/apt.package.rst
new file mode 100644
index 0000000..ec7ed36
--- /dev/null
+++ b/doc/source/library/apt.package.rst
@@ -0,0 +1,122 @@
+:mod:`apt.package` --- Classes for package handling
+====================================================
+
+
+.. automodule:: apt.package
+
+
+The Package class
+-----------------
+.. autoclass:: Package
+ :members:
+
+ .. note::
+
+ Several methods have been deprecated in version 0.7.9 of python-apt,
+ please see the :class:`Version` class for the new alternatives.
+
+The Version class
+-----------------
+.. autoclass:: Version
+ :members:
+
+
+Dependency Information
+----------------------
+.. autoclass:: BaseDependency
+ :members:
+
+.. class:: Dependency
+
+ The dependency class represents a Or-Group of dependencies. It provides
+ an attribute to access the :class:`BaseDependency` object for the available
+ choices.
+
+ .. attribute:: or_dependencies
+
+ A list of :class:`BaseDependency` objects which could satisfy the
+ requirement of the Or-Group.
+
+
+Origin Information
+-------------------
+.. class:: Origin
+
+ The :class:`Origin` class provides access to the origin of the package.
+ It allows you to check the component, archive, the hostname, and even if
+ this package can be trusted.
+
+ .. attribute:: archive
+
+ The archive (eg. unstable)
+
+ .. attribute:: component
+
+ The component (eg. main)
+
+ .. attribute:: label
+
+ The Label, as set in the Release file
+
+ .. attribute:: origin
+
+ The Origin, as set in the Release file
+
+ .. attribute:: site
+
+ The hostname of the site.
+
+ .. attribute:: trusted
+
+ Boolean value whether this is trustworthy. An origin can be trusted, if
+ it provides a GPG-signed Release file and the GPG-key used is in the
+ keyring used by apt (see apt-key).
+
+
+
+The Record class
+-----------------
+.. autoclass:: Record
+ :members:
+
+ .. note::
+ .. versionchanged:: 0.7.100
+ This class is a subclass of :class:`collections.Mapping` when used
+ in Python 2.6 or newer.
+
+ .. describe:: record[name]
+
+ Return the value of the field with the name *name*.
+
+ .. describe:: name in record
+
+ Return whether a field *name* exists in record.
+
+ .. describe:: len(record)
+
+ The number of fields in the record
+
+ .. describe:: str(record)
+
+ Display the record as a string
+
+
+Examples
+---------
+.. code-block:: python
+
+ import apt
+
+ cache = apt.Cache()
+ pkg = cache['python-apt'] # Access the Package object for python-apt
+ print('python-apt is trusted:', pkg.candidate.origins[0].trusted)
+
+ # Mark python-apt for install
+ pkg.mark_install()
+
+ print('python-apt is marked for install:', pkg.marked_install)
+
+ print('python-apt is (summary):', pkg.candidate.summary)
+
+ # Now, really install it
+ cache.commit()
diff --git a/doc/source/library/apt.progress.base.rst b/doc/source/library/apt.progress.base.rst
new file mode 100644
index 0000000..7d43fe9
--- /dev/null
+++ b/doc/source/library/apt.progress.base.rst
@@ -0,0 +1,335 @@
+:mod:`apt.progress.base` --- Abstract classes for progress reporting
+====================================================================
+.. module:: apt.progress.base
+
+This module provides base classes for progress handlers from which all
+progress classes should inherit from. Progress reporting classes not
+inheriting from those classes may not work and are not supported.
+
+When creating a subclass of one of those classes, all overridden methods should
+call the parent's method first before doing anything else, because the parent
+method may have to set some attributes. Subclasses not doing so may not work
+correctly or may not work at all and are completely unsupported.
+
+AcquireProgress
+---------------
+.. class:: AcquireProgress
+
+ A monitor object for downloads controlled by the Acquire class. This base
+ class does nothing and should only be used as a base class to inherit
+ from. Instances of this class can be passed to the constructor of
+ :class:`apt_pkg.Acquire` and the Acquire object then uses it to report
+ its progress.
+
+ This class provides several methods which may be overridden by subclasses
+ to implement progress reporting:
+
+ .. method:: done(item: apt_pkg.AcquireItemDesc)
+
+ Invoked when an item is successfully and completely fetched.
+
+ .. method:: fail(item: apt_pkg.AcquireItemDesc)
+
+ Invoked when the process of fetching an item encounters a fatal error
+ like a non existing file or no connection to the server.
+
+ .. method:: fetch(item: apt_pkg.AcquireItemDesc)
+
+ Invoked when some of the item's data is fetched. This normally means
+ that the file is being fetched now and e.g. the headers have been
+ retrieved already.
+
+ .. method:: ims_hit(item: apt_pkg.AcquireItemDesc)
+
+ Invoked when an item is confirmed to be up-to-date. For instance,
+ when an HTTP download is informed that the file on the server was
+ not modified.
+
+ .. method:: media_change(media: str, drive: str) -> bool
+
+ Prompt the user to change the inserted removable media. This function
+ is called whenever a media change is needed to ask the user to insert
+ the needed media.
+
+ The parameter *media* decribes the name of the media type that
+ should be changed, whereas the parameter *drive* should be the
+ identifying name of the drive whose media should be changed.
+
+ This method should not return until the user has confirmed to the user
+ interface that the media change is complete. It must return True if
+ the user confirms the media change, or False to cancel it.
+
+ .. method:: pulse(owner: apt_pkg.Acquire) -> bool
+
+ This method gets invoked while the Acquire progress given by the
+ parameter *owner* is underway. It should display information about
+ the current state. It must return ``True`` to continue the acquistion
+ or ``False`` to cancel it. This base implementation always returns
+ ``True``.
+
+ .. method:: start()
+
+ Invoked when the Acquire process starts running.
+
+ .. method:: stop()
+
+ Invoked when the Acquire process stops running.
+
+ In addition to those methods, this class provides several attributes which
+ are set automatically and represent the fetch progress:
+
+ .. attribute:: current_bytes
+
+ The number of bytes fetched.
+
+ .. attribute:: current_cps
+
+ The current rate of download, in bytes per second.
+
+ .. attribute:: current_items
+
+ The number of items that have been successfully downloaded.
+
+ .. attribute:: elapsed_time
+
+ The amount of time that has elapsed since the download started.
+
+ .. attribute:: fetched_bytes
+
+ The total number of bytes accounted for by items that were
+ successfully fetched.
+
+ .. attribute:: last_bytes
+
+ The number of bytes fetched as of the previous call to pulse(),
+ including local items.
+
+ .. attribute:: total_bytes
+
+ The total number of bytes that need to be fetched. This member is
+ inaccurate, as new items might be enqueued while the download is
+ in progress!
+
+ .. attribute:: total_items
+
+ The total number of items that need to be fetched. This member is
+ inaccurate, as new items might be enqueued while the download is
+ in progress!
+
+
+CdromProgress
+-------------
+.. class:: CdromProgress
+
+ Base class for reporting the progress of adding a cdrom which could be
+ used with apt_pkg.Cdrom to produce an utility like apt-cdrom.
+
+ Methods defined here:
+
+ .. method:: ask_cdrom_name() -> str
+
+ Ask for the name of the cdrom. This method is called when a CD-ROM
+ is added (e.g. via :meth:`apt_pkg.Cdrom.add`) and no label for the
+ CD-ROM can be found.
+
+ Implementations should request a label from the user (e.g. via
+ :func:`raw_input`) and return this label from the function. The
+ operation can be cancelled if the function returns ``None`` instead
+ of a string.
+
+ .. method:: change_cdrom() -> bool
+
+ Ask for the CD-ROM to be changed. This method should return ``True``
+ if the CD-ROM has been changed or ``False`` if the CD-ROM has not been
+ changed and the operation should be cancelled. This base implementation
+ returns ``False`` and thus cancels the operation.
+
+ .. method:: update(text: str, current: int)
+
+ Periodically invoked in order to update the interface and give
+ information about the progress of the operation.
+
+ This method has two parameters. The first parameter *text* defines
+ the text which should be displayed to the user as the progress
+ message. The second parameter *current* is an integer describing how
+ many steps have been completed already.
+
+ .. attribute:: total_steps
+
+ The number of total steps, set automatically by python-apt. It may be
+ used in conjunction with the parameter *current* of the :meth:`update`
+ method to show how far the operation progressed.
+
+
+OpProgress
+----------
+.. class:: OpProgress
+
+ OpProgress classes are used for reporting the progress of operations
+ such as opening the cache. It is based on the concept of one operation
+ consisting of a series of sub operations.
+
+ Methods defined here:
+
+ .. method:: done()
+
+ Called once an operation has been completed.
+
+ .. method:: update([percent=None])
+
+ Called periodically to update the user interface. This function should
+ use the attributes defined below to display the progress information.
+
+ The optional parameter *percent* is included for compatibility
+ reasons and may be removed at a later time.
+
+ The following attributes are available and are changed by the classes
+ wanting to emit progress:
+
+ .. attribute:: major_change
+
+ An automatically set boolean value describing whether the current call
+ to update is caused by a major change. In this case, the last operation
+ has finished.
+
+ .. attribute:: op
+
+ An automatically set string which describes the current operation in
+ an human-readable way.
+
+ .. attribute:: percent
+
+ An automatically set float value describing how much of the operation
+ has been completed, in percent.
+
+ .. attribute:: subop
+
+ An automatically set string which describes the current sub-operation
+ in an human-readable way.
+
+
+InstallProgress
+---------------
+.. class:: InstallProgress
+
+ InstallProgress classes make it possible to monitor the progress of dpkg
+ and APT and emit information at certain stages. It uses file descriptors
+ to read the status lines from APT/dpkg and parses them and afterwards calls
+ the callback methods.
+
+ Subclasses should override the following methods in order to implement
+ progress reporting:
+
+ .. method:: conffile(current, new)
+
+ Called when a conffile question from dpkg is detected.
+
+ .. note::
+
+ This part of the API is semi-stable and may be extended with 2 more
+ parameters before the release of 0.7.100.
+
+ .. method:: error(pkg, errormsg)
+
+ (Abstract) Called when a error is detected during the install.
+
+ The following method should be overridden to implement progress reporting
+ for dpkg-based runs i.e. calls to :meth:`run` with a filename:
+
+ .. method:: processing(pkg, stage)
+
+ This method is called just before a processing stage starts. The
+ parameter *pkg* is the name of the package and the parameter *stage*
+ is one of the stages listed in the dpkg manual under the status-fd
+ option, i.e. "upgrade", "install" (both sent before unpacking),
+ "configure", "trigproc", "remove", "purge".
+
+ .. method:: dpkg_status_change(pkg: str, status: str)
+
+ This method is called whenever the dpkg status of the package
+ changes. The parameter *pkg* is the name of the package and the
+ parameter *status* is one of the status strings used in the status
+ file (:file:`/var/lib/dpkg/status`) and documented
+ in :manpage:`dpkg(1)`.
+
+ The following methods should be overridden to implement progress reporting
+ for :meth:`run` calls with an :class:`apt_pkg.PackageManager` object as
+ their parameter:
+
+ .. method:: status_change(pkg, percent, status)
+
+ This method implements progress reporting for package installation by
+ APT and may be extended to dpkg at a later time.
+
+ This method takes two parameters: The parameter *percent* is a float
+ value describing the overall progress and the parameter *status* is a
+ string describing the current status in an human-readable manner.
+
+ .. method:: start_update()
+
+ This method is called before the installation of any package starts.
+
+ .. method:: finish_update()
+
+ This method is called when all changes have been applied.
+
+ There are also several methods which are fully implemented and should not
+ be overridden by subclasses unless the subclass has very special needs:
+
+ .. method:: fork() -> int
+
+ Fork a child process and return 0 to the child process and the PID of
+ the child to the parent process. This implementation just calls
+ :func:`os.fork` and returns its value.
+
+ .. method:: run(obj)
+
+ This method runs install actions. The parameter *obj* may either
+ be a PackageManager object in which case its **do_install()** method is
+ called or the path to a deb file.
+
+ If the object is a :class:`apt_pkg.PackageManager`, the functions
+ returns the result of calling its ``do_install()`` method. Otherwise,
+ the function returns the exit status of dpkg. In both cases, ``0``
+ means that there were no problems and ``!= 0`` means that there were
+ issues.
+
+ .. method:: update_interface()
+
+ This method is responsible for reading the status from dpkg/APT and
+ calling the correct callback methods. Subclasses should not override
+ this method.
+
+ .. method:: wait_child()
+
+ This method is responsible for calling :meth:`update_interface` from
+ time to time. It exits once the child has exited. The return value
+ is the full status returned by :func:`os.waitpid` (not only the
+ return code). Subclasses should not override this method.
+
+ The class also provides several attributes which may be useful:
+
+ .. attribute:: percent
+
+ The percentage of completion as it was in the last call to
+ :meth:`status_change`.
+
+ .. attribute:: status
+
+ The status string passed in the last call to :meth:`status_change`.
+
+ .. attribute:: select_timeout
+
+ Used in :meth:`wait_child` to when calling :func:`select.select`
+ on dpkg's/APT's status descriptor. Subclasses may set their own value
+ if needed.
+
+ .. attribute:: statusfd
+
+ A readable :class:`file` object from which the status information from
+ APT or dpkg is read.
+
+ .. attribute:: writefd
+
+ A writable :class:`file` object to which dpkg or APT write their status
+ information.
diff --git a/doc/source/library/apt.progress.text.rst b/doc/source/library/apt.progress.text.rst
new file mode 100644
index 0000000..4e051e3
--- /dev/null
+++ b/doc/source/library/apt.progress.text.rst
@@ -0,0 +1,21 @@
+:mod:`apt.progress.text` --- Progress reporting for text interfaces
+===================================================================
+.. automodule:: apt.progress.text
+
+
+Acquire Progress Reporting
+--------------------------
+.. autoclass:: AcquireProgress
+ :members:
+
+
+CD-ROM Progress Reporting
+--------------------------
+.. autoclass:: CdromProgress
+ :members:
+
+Operation Progress Reporting
+-----------------------------
+.. autoclass:: OpProgress
+ :members:
+
diff --git a/doc/source/library/apt_inst.rst b/doc/source/library/apt_inst.rst
new file mode 100644
index 0000000..6ba330a
--- /dev/null
+++ b/doc/source/library/apt_inst.rst
@@ -0,0 +1,323 @@
+:mod:`apt_inst` - Working with local Debian packages
+====================================================
+.. module:: apt_inst
+
+This module provides useful classes and functions to work with archives,
+modelled after the :class:`tarfile.TarFile` class. For working with Debian
+packages, the :class:`DebFile` class should be used as it provides easy access
+to the control.tar.* and data.tar.* members.
+
+The classes are mostly modeled after the :class:`tarfile.TarFile` class and
+enhanced with APT-specific methods. Because APT only provides a stream based
+view on a tar archive, this module's :class:`TarFile` class only provides a
+very small subset of those functions.
+
+Exceptions
+----------
+
+.. class:: Error
+
+ This is the same class as :class:`apt_pkg.Error`, provided here for
+ convenience.
+
+AR Archives
+-----------
+.. class:: ArArchive(file)
+
+ An ArArchive object represents an archive in the 4.4 BSD AR format,
+ which is used for e.g. deb packages.
+
+ The parameter *file* may be a string specifying the path of a file, or
+ a :class:`file`-like object providing the :meth:`fileno` method. It may
+ also be an int specifying a file descriptor (returned by e.g.
+ :func:`os.open`). The recommended way is to pass in the path to the file.
+
+ ArArchive (and its subclasses) support the iterator protocol, meaning that
+ an :class:`ArArchive` object can be iterated over yielding the members in
+ the archive (same as :meth:`getmembers`).
+
+ .. describe:: archive[key]
+
+ Return a ArMember object for the member given by *key*. Raise
+ LookupError if there is no ArMember with the given name.
+
+ .. describe:: key in archive
+
+ Return True if a member with the name *key* is found in the archive, it
+ is the same function as :meth:`getmember`.
+
+ .. method:: extract(name[, target: str]) -> bool
+
+ Extract the member given by *name* into the directory given by
+ *target*. If the extraction failed, an error is raised. Otherwise,
+ the method returns True if the owner could be set or False if the
+ owner could not be changed. It may also raise LookupError if there
+ is no member with the given name.
+
+ The parameter *target* is completely optional. If it is not given, the
+ function extracts into the current directory.
+
+ .. method:: extractall([target: str]) -> bool
+
+ Extract all into the directory given by target or the current
+ directory if target is not given. If the extraction failed, an error
+ is raised. Otherwise, the method returns True if the owner could be
+ set or False if the owner could not be changed.
+
+ .. method:: extractdata(name: str) -> bytes
+
+ Return the contents of the member given by *name*, as a bytes object.
+ Raise LookupError if there is no ArMember with the given name.
+
+ .. method:: getmember(name: str) -> ArMember
+
+ Return a ArMember object for the member given by *name*. Raise
+ LookupError if there is no ArMember with the given name.
+
+ .. method:: getmembers() -> list
+
+ Return a list of all members in the AR archive.
+
+ .. method:: getnames() -> list
+
+ Return a list of the names of all members in the AR archive.
+
+ .. method:: gettar(name: str, comp: str) -> TarFile
+
+ Return a TarFile object for the member given by *name* which will be
+ decompressed using the compression algorithm given by *comp*.
+ This is almost equal to::
+
+ member = arfile.getmember(name)
+ tarfile = TarFile(file, member.start, member.size, 'gzip')'
+
+ It just opens a new TarFile on the given position in the stream.
+
+.. class:: ArMember
+
+ An ArMember object represents a single file within an AR archive. For
+ Debian packages this can be e.g. control.tar.gz. This class provides
+ information about this file, such as the mode and size. It has no
+ constructor.
+
+ .. attribute:: gid
+
+ The group id of the owner.
+
+ .. attribute:: mode
+
+ The mode of the file.
+
+ .. attribute:: mtime
+
+ Last time of modification.
+
+ .. attribute:: name
+
+ The name of the file.
+
+ .. attribute:: size
+
+ The size of the files.
+
+ .. attribute:: start
+
+ The offset in the archive where the file starts.
+
+ .. attribute:: uid
+
+ The user id of the owner.
+
+Debian Packages
+---------------
+.. class:: DebFile(file)
+
+ A DebFile object represents a file in the .deb package format. It inherits
+ :class:`ArArchive`. In addition to the attributes and methods from
+ :class:`ArArchive`, DebFile provides the following methods:
+
+ .. attribute:: control
+
+ The :class:`TarFile` object associated with the control.tar.gz member.
+
+ .. attribute:: data
+
+ The :class:`TarFile` object associated with the
+ data.tar.{gz,bz2,lzma,xz} member.
+
+ .. attribute:: debian_binary
+
+ The package version, as contained in debian-binary.
+
+Tar Archives
+-------------
+.. class:: TarFile(file[, min: int, max: int, comp: str])
+
+ A TarFile object represents a single .tar file stream.
+
+ The parameter *file* may be a string specifying the path of a file, or
+ a :class:`file`-like object providing the :meth:`fileno` method. It may
+ also be an int specifying a file descriptor (returned by e.g.
+ :func:`os.open`).
+
+ The parameter *min* describes the offset in the file where the archive
+ begins and the parameter *max* is the size of the archive.
+
+ The compression of the archive is set by the parameter *comp*. It can
+ be set to any program supporting the -d switch, the default being gzip.
+
+ .. method:: extractall([rootdir: str]) -> True
+
+ Extract the archive in the current directory. The argument *rootdir*
+ can be used to change the target directory.
+
+ .. method:: extractdata(member: str) -> bytes
+
+ Return the contents of the member, as a bytes object. Raise
+ LookupError if there is no member with the given name.
+
+ .. method:: go(callback: callable[, member: str]) -> True
+
+ Go through the archive and call the callable *callback* for each
+ member with 2 arguments. The first argument is the :class:`TarMember`
+ and the second one is the data, as bytes.
+
+ The optional parameter *member* can be used to specify the member for
+ which call the callback. If not specified, it will be called for all
+ members. If specified and not found, LookupError will be raised.
+
+.. class:: TarMember
+
+ Represent a single member of a 'tar' archive.
+
+ This class which has been modelled after :class:`tarfile.TarInfo`
+ represents information about a given member in an archive.
+
+ .. method:: isblk()
+
+ Determine whether the member is a block device.
+
+ .. method:: ischr()
+
+ Determine whether the member is a character device.
+
+ .. method:: isdev()
+
+ Determine whether the member is a device (block,character or FIFO).
+
+ .. method:: isdir()
+
+ Determine whether the member is a directory.
+
+ .. method:: isfifo()
+
+ Determine whether the member is a FIFO.
+
+ .. method:: isfile()
+
+ Determine whether the member is a regular file.
+
+ .. method:: islnk()
+
+ Determine whether the member is a hardlink.
+
+ .. method:: isreg()
+
+ Determine whether the member is a regular file, same as isfile().
+
+ .. method:: issym()
+
+ Determine whether the member is a symbolic link.
+
+ .. attribute:: gid
+
+ The owner's group id
+
+ .. attribute:: linkname
+
+ The target of the link.
+
+ .. attribute:: major
+
+ The major ID of the device.
+
+ .. attribute:: minor
+
+ The minor ID of the device.
+
+ .. attribute:: mode
+
+ The mode (permissions).
+
+ .. attribute:: mtime
+
+ Last time of modification.
+
+ .. attribute:: name
+
+ The name of the file.
+
+ .. attribute:: size
+
+ The size of the file.
+
+ .. attribute:: uid
+
+ The owner's user id.
+
+
+
+Removed functions
+---------------------
+The following functions have been removed in python-apt 0.8.
+They are listed here to help developers port their applications to the new
+API which is completely different. For this purpose each function documentation
+includes an example showing how the function can be replaced.
+
+.. function:: arCheckMember(file, membername)
+
+ This function has been replaced by using the :keyword:`in` check on an
+ :class:`ArArchive` object::
+
+ member in ArArchive(file)
+
+.. function:: debExtract(file, func, chunk)
+
+ This function has been replaced by the :meth:`TarFile.go`
+ method. The following example shows the old code and the new code::
+
+ debExtract(open("package.deb"), my_callback, "data.tar.gz") #old
+
+ DebFile("package.deb").data.go(my_callback)
+
+ Please note that the signature of the callback is different in
+ :meth:`TarFile.go`.
+
+.. function:: tarExtract(file,func,comp)
+
+ This function has been replaced by the :meth:`TarFile.go`
+ method. The following example shows the old code and the new code::
+
+ tarExtract(open("archive.tar.gz"), my_callback, "gzip") #old
+ TarFile("archive.tar.gz", 0, 0, "gzip").go(my_callback)
+
+ Please note that the signature of the callback is different in
+ :meth:`TarFile.go`, it now expects a :class:`TarMember` and a bytestring
+ of the data.
+
+.. function:: debExtractArchive(file, rootdir)
+
+ This function has been replaced by :meth:`TarFile.extractall` and
+ :attr:`DebFile.data`::
+
+ debExtractArchive(open("package.deb"), rootdir) # old
+ DebFile("package.deb").data.extractall(rootdir) # new
+
+.. function:: debExtractControl(file[, member='control'])
+
+ This function has been replaced by :attr:`DebFile.control` and
+ :meth:`TarFile.extractdata`. In the following example, both commands
+ return the contents of the control file::
+
+ debExtractControl(open("package.deb"))
+ DebFile("package.deb").control.extractdata("control")
diff --git a/doc/source/library/apt_pkg.rst b/doc/source/library/apt_pkg.rst
new file mode 100644
index 0000000..4290180
--- /dev/null
+++ b/doc/source/library/apt_pkg.rst
@@ -0,0 +1,2904 @@
+:mod:`apt_pkg` --- The low-level bindings for apt-pkg
+=====================================================
+.. module:: apt_pkg
+
+The apt_pkg extensions provides a more low-level way to work with apt. It can
+do everything apt can, and is written in C++. It has been in python-apt since
+the beginning.
+
+Module Initialization
+---------------------
+
+Initialization is needed for most functions, but not for all of them. Some can
+be called without having run init*(), but will not return the expected value.
+
+.. function:: init_config
+
+ Initialize the configuration of apt. This is needed for most operations.
+
+.. function:: init_system
+
+ Initialize the system.
+
+.. function:: init
+
+ A short cut to calling :func:`init_config` and :func:`init_system`. You
+ can use this if you do not use the command line parsing facilities provided
+ by :func:`parse_commandline`, otherwise call :func:`init_config`, parse
+ the commandline afterwards and finally call :func:`init_system`.
+
+
+Exceptions
+----------
+.. autoclass:: Error
+
+.. autoclass:: CacheMismatchError
+
+
+Working with the cache
+----------------------
+.. class:: Cache([progress: apt.progress.base.OpProgress])
+
+ A Cache object represents the cache used by APT which contains information
+ about packages. The object itself provides no means to modify the cache or
+ the installed packages, see the classes :class:`DepCache` and
+ :class:`PackageManager` for such functionality.
+
+ The constructor takes an optional argument which must be a subclass of
+ :class:`apt.progress.base.OpProgress`. This object will then be used to
+ display information during the cache opening process (or possible creation
+ of the cache). It may also be ``None``, in which case no progress will
+ be emitted. If not given, progress will be printed to standard output.
+
+ .. note::
+
+ The cache supports colon-separated name:architecture pairs. For
+ normal architectures, they are equal to a (name, architecture)
+ tuple. For the "any" architecture behavior is different, as
+ "name:any" is equivalent to ("name:any", "any"). This is done so
+ that "name:any" matches all packages with that name which have
+ Multi-Arch: allowed set.
+
+ .. describe:: cache[pkgname]
+
+ Return the :class:`Package()` object for the package name given by
+ *pkgname*. If *pkgname* includes a colon, the part after the colon
+ is used as the architecture.
+
+ .. describe:: cache[name, architecture]
+
+ Return the :class:`Package()` object for the package with the given
+ name and architecture.
+
+ .. versionadded: 0.8.0
+
+ .. describe:: pkgname in cache
+
+ Check whether a package with the name given by *pkgname* exists in
+ the cache for the native architecture. If *pkgname* includes a
+ colon, the part after the colon is used as the architecture.
+
+ .. describe:: (name, architecture) in cache
+
+ Check whether a package with the given name and architecture exists
+ in the cache.
+
+ .. versionadded: 0.8.0
+
+ .. method:: update(progress, sources [, pulse_interval]) -> bool
+
+ Update the index files used by the cache. A call to this method
+ does not affect the current Cache object, instead a new one
+ should be created in order to use the changed index files.
+
+ The parameter *progress* takes an
+ :class:`apt.progress.base.AcquireProgress` object which will display
+ the progress of fetching the index files. The parameter *sources* takes
+ a :class:`SourceList` object which lists the sources. The parameter
+ *progress* takes an integer describing the interval (in microseconds)
+ in which the pulse() method of the *progress* object will be called.
+
+ .. attribute:: depends_count
+
+ The total number of dependencies stored in the cache.
+
+ .. attribute:: file_list
+
+ A list of all :class:`PackageFile` objects stored in the cache.
+
+ .. attribute:: group_count
+
+ The number of groups in the cache.
+
+ .. versionadded: 0.8.0
+
+ .. attribute:: groups
+
+ A sequence of :class:`Group` objects, implemented as a
+ :class:`GroupList` object.
+
+ .. versionadded: 0.8.0
+
+ .. class:: GroupList
+
+ A simple sequence-like object which only provides a length and
+ an implementation of ``__getitem__`` for accessing groups at
+ a certain index. Apart from being iterable, it can be used in
+ the following ways:
+
+ .. versionadded: 0.8.0
+
+ .. describe:: list[index]
+
+ Get the :class:`Group` object for the group at the position
+ given by *index* in the GroupList *list*.
+
+ .. describe:: len(list)
+
+ Return the length of the GroupList object *list*.
+
+
+ .. attribute:: is_multi_arch
+
+ An attribute determining whether the cache supports multi-arch.
+
+ .. versionadded: 0.8.0
+
+ .. attribute:: package_count
+
+ The total number of packages available in the cache. This value is
+ equal to the length of the list provided by the :attr:`packages`
+ attribute.
+
+ .. attribute:: package_file_count
+
+ The total number of Packages files available (the Packages files
+ listing the packages). This is the same as the length of the list in
+ the attribute :attr:`file_list`.
+
+ .. attribute:: packages
+
+ A sequence of :class:`Package` objects, implemented as a
+ :class:`PackageList` object.
+
+ .. class:: PackageList
+
+ A simple sequence-like object which only provides a length and
+ an implementation of ``__getitem__`` for accessing packages at
+ a certain index. Apart from being iterable, it can be used in
+ the following ways:
+
+ .. describe:: list[index]
+
+ Get the :class:`Package` object for the package at the position
+ given by *index* in the PackageList *list*.
+
+ .. describe:: len(list)
+
+ Return the length of the PackageList object *list*.
+
+ .. attribute:: provides_count
+
+ The number of provided packages.
+
+ .. attribute:: ver_file_count
+
+ The total number of ``(Version, PackageFile)`` relations stored in
+ the cache.
+
+ .. attribute:: version_count
+
+ The total number of package versions available in the cache.
+
+Managing the cache with :class:`DepCache`
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. class:: DepCache(cache: apt_pkg.Cache)
+
+ A DepCache object provides access to more information about the
+ objects made available by the :class:`Cache` object as well as
+ means to mark packages for removal and installation, among other
+ actions.
+
+ The constructor takes a single argument which specifies the
+ :class:`Cache` object the new object shall be related to. While
+ it is theoretically possible to create multiple DepCache objects
+ for the same cache, they will not be independent from each other
+ since they all access the same underlying C++ object.
+
+ Objects of this type provide several methods. Most of those methods
+ are safe to use and should never raise any exception (all those
+ methods for requesting state information or marking changes). If a
+ method is expected to raise an exception, it will be stated in the
+ description.
+
+ If an object of a different cache is passed, :class:`CacheMismatchError`
+ is raised.
+
+ .. method:: commit(acquire_progress, install_progress)
+
+ Commit all marked changes, while reporting the progress of
+ fetching packages via the :class:`apt.progress.base.AcquireProgress`
+ object given by *acquire_progress* and reporting the installation
+ of the package using the :class:`apt.progress.base.InstallProgress`
+ object given by *install_progress*.
+
+ If this fails, an exception of the type :exc:`SystemError` will
+ be raised.
+
+ .. method:: fix_broken() -> bool
+
+ Try to fix all broken packages in the cache and return ``True`` in
+ case of success. If an error occurred, a :exc:`SystemError`
+ exception is raised.
+
+ .. method:: get_candidate_ver(pkg: Package) -> Version
+
+ Return the candidate version for the package given by the parameter
+ *pkg* as a :class:`Version` object. The default candidate for a
+ package is the version with the highest pin, although a different
+ one may be set using :meth:`set_candidate_ver`. If no candidate
+ can be found, return ``None`` instead.
+
+ .. method:: init(progress: apt.progress.base.OpProgress)
+
+ Initialize the DepCache. This is done automatically when the
+ cache is opened, but sometimes it may be useful to reinitialize
+ the DepCache. Like the constructor of :class:`Cache`, this
+ function takes a single :class:`apt.progress.base.OpProgress`
+ object to display progress information.
+
+ .. method:: read_pinfile(file: str)
+
+ A proxy function which calls the method :meth:`Policy.read_pinfile` of
+ the :class:`Policy` object used by this object. This method raises
+ a :exc:`SystemError` exception if the file could not be parsed.
+
+ .. method:: set_candidate_ver(pkg: Package, version: Version) -> bool
+
+ Set the candidate version of the package given by the :class:`Package`
+ object *pkg* to the version given by the :class:`Version` object
+ *version* and return ``True``. If odd things happen, this function
+ may raise a :exc:`SystemError` exception, but this should not
+ happen in normal usage. See :meth:`get_candidate_ver` for a way
+ to retrieve the candidate version of a package.
+
+ .. method:: upgrade([dist_upgrade=False]) -> bool
+
+ Mark the packages for upgrade under the same conditions
+ :program:`apt-get` does. If *dist_upgrade* is ``True``, also
+ allow packages to be upgraded if they require installation/removal
+ of other packages; just like apt-get dist-upgrade.
+
+ Despite returning a boolean value, this raises :exc:`SystemError` and
+ does not return ``False`` if an error occurred.
+
+ The following methods can mark a single package for installation,
+ removal, etc:
+
+ .. method:: mark_auto(pkg: Package)
+
+ Mark the :class:`Package` *pkg* as automatically installed.
+
+ .. method:: mark_keep(pkg: Package)
+
+ Mark the :class:`Package` *pkg* for keep.
+
+ .. method:: mark_delete(pkg: Package[, purge])
+
+ Mark the :class:`Package` *pkg* for delete. If *purge* is True,
+ the configuration files will be removed as well.
+
+ .. method:: mark_install(pkg: Package[, auto_inst=True[, from_user=True]])
+
+ Mark the :class:`Package` *pkg* for install, and, if *auto_inst*
+ is ``True``, its dependencies as well. If *from_user* is ``True``,
+ the package will **not** be marked as automatically installed.
+
+ .. method:: set_reinstall(pkg: Package)
+
+ Set if the :class:`Package` *pkg* should be reinstalled.
+
+ The following methods can be used to check the state of a package:
+
+ .. method:: is_auto_installed(pkg: Package) -> bool
+
+ Return ``True`` if the package is automatically installed, that
+ is, as a dependency of another package.
+
+ .. method:: is_garbage(pkg: Package) -> bool
+
+ Return ``True`` if the package is garbage, that is, if it was
+ automatically installed and no longer referenced by other packages.
+
+ .. method:: is_inst_broken(pkg: Package) -> bool
+
+ Return ``True`` if the package is broken on the current install. This
+ takes changes which have not been marked not into account.
+
+ .. method:: is_now_broken(pkg: Package) -> bool
+
+ Return ``True`` if the package is now broken, that is, if the package
+ is broken if the marked changes are applied.
+
+ .. method:: is_upgradable(pkg: Package) -> bool
+
+ Return ``True`` if the package is upgradable, the package can then
+ be marked for upgrade by calling the method :meth:`mark_install`.
+
+ .. method:: marked_delete(pkg: Package) -> bool
+
+ Return ``True`` if the package is marked for delete.
+
+ .. method:: marked_downgrade(pkg: Package) -> bool
+
+ Return ``True`` if the package should be downgraded.
+
+ .. method:: marked_install(pkg: Package) -> bool
+
+ Return ``True`` if the package is marked for install.
+
+ .. method:: marked_keep(pkg: Package) -> bool
+
+ Return ``True`` if the package is marked for keep.
+
+ .. method:: marked_reinstall(pkg: Package) -> bool
+
+ Return ``True`` if the package should be reinstalled.
+
+ .. method:: marked_upgrade(pkg: Package) -> bool
+
+ Return ``True`` if the package is marked for upgrade.
+
+ .. method:: phasing_applied(pkg: Package) -> bool
+
+ Return ``True`` if the package update is being phased.
+
+ DepCache objects also provide several attributes containing information
+ on the marked changes:
+
+ .. attribute:: keep_count
+
+ Integer, number of packages marked as keep
+
+ .. attribute:: inst_count
+
+ Integer, number of packages marked for installation.
+
+ .. attribute:: del_count
+
+ Number of packages which should be removed.
+
+ .. attribute:: broken_count
+
+ Number of packages which are broken.
+
+ .. attribute:: usr_size
+
+ The size required for the changes on the filesystem. If you install
+ packages, this is positive, if you remove them its negative.
+
+ .. attribute:: deb_size
+
+ The size of the packages which are needed for the changes to be
+ applied.
+
+ .. attribute:: policy
+
+ The underlying :class:`Policy` object used by the :class:`DepCache` to
+ select candidate versions.
+
+Installing with :class:`PackageManager`
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. class:: PackageManager(depcache)
+
+ Abstraction of a package manager. This object takes care of retrieving
+ packages, ordering the installation, and calling the package manager to
+ do the actual installation.
+
+ .. method:: get_archives(fetcher, list, records) -> bool
+
+ Add all packages marked for installation (or upgrade, anything
+ which needs a download) to the :class:`Acquire` object referenced
+ by *fetcher*.
+
+ The parameter *list* specifies a :class:`SourceList` object which
+ is used to retrieve the information about the archive URI for the
+ packages which will be fetched.
+
+ The parameter *records* takes a :class:`PackageRecords` object which
+ will be used to look up the file name of the package.
+
+ .. method:: do_install(status_fd: int) -> int
+
+ Install the packages and return one of the class constants
+ :attr:`RESULT_COMPLETED`, :attr:`RESULT_FAILED`,
+ :attr:`RESULT_INCOMPLETE`. The argument *status_fd* can be used
+ to specify a file descriptor that APT will write status information
+ on (see README.progress-reporting in the apt source code for
+ information on what will be written there).
+
+ .. method:: fix_missing() -> bool
+
+ Fix the installation if a package could not be downloaded.
+
+ .. attribute:: RESULT_COMPLETED
+
+ A constant for checking whether the result of the call to
+ :meth:`do_install` is 'failed'.
+
+ .. attribute:: RESULT_FAILED
+
+ A constant for checking whether the result of the call to
+ :meth:`do_install` is 'failed'.
+
+ .. attribute:: RESULT_INCOMPLETE
+
+ A constant for checking whether the result of the call to
+ :meth:`do_install` is 'incomplete'.
+
+ All instances of this class also support the following methods:
+
+ .. note::
+
+ This methods are provided mainly for subclassing purposes
+ and should not be used in most programs. This class is a
+ subclass of an internal :class:`_PackageManager` which does
+ not provide that methods. As the public C++ API creates such
+ an object without those methods, you should not rely on those
+ methods to be available unless you used the constructor of
+ :class:`PackageManager` to create the object.
+
+ .. method:: configure(pkg: Package) -> bool
+
+ Notify the package manager that the :class:`Package` given
+ by *pkg* is to be configured. Must return a ``True`` value
+ or ``None`` to continue, or a value which is ``False`` if
+ evaluated as boolean to abort.
+
+ .. versionadded:: 0.8.0
+
+ .. method:: install(pkg: Package, filename: str) -> bool
+
+ Notify the package manager that the :class:`Package` given
+ by *pkg* is to be installed from the .deb located at
+ *filename*. Must return a ``True`` value or ``None`` to
+ continue, or a value which is ``False`` if evaluated as
+ boolean to abort.
+
+
+ .. versionadded:: 0.8.0
+
+ .. method:: remove(pkg: Package, purge: bool) -> bool
+
+ Notify the package manager that the :class:`Package` given
+ by *pkg* is to be removed. If *purge* is ``True``, the package
+ shall be purged. Must return a ``True`` value or ``None`` to
+ continue, or a value which is ``False`` if evaluated as boolean
+ to abort.
+
+
+ .. versionadded:: 0.8.0
+
+ .. method:: go(status_fd: int) -> bool
+
+ Start dpkg, writing status information to the file descriptor
+ given by *status_fd*. Must return a ``True`` value or ``None`` to
+ continue, or a value which is ``False`` if evaluated as boolean
+ to abort.
+
+ .. versionadded:: 0.8.0
+
+ .. method:: reset()
+
+ Reset the package manager for a new round.
+
+ .. versionadded:: 0.8.0
+
+
+Installation ordering with :class:`OrderList`
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. class:: OrderList(depcache: DepCache)
+
+ Represent a :c:type:`pkgOrderList`, used for installation
+ ordering. This class provides several methods and attributes,
+ is complicated and should not be used by normal programs.
+
+ .. versionadded:: 0.8.0
+
+ This class is a sequence and supports the following operations:
+
+ .. describe:: list[index]
+
+ Get the package at the given index in the list. Negative
+ index is supported.
+
+ .. describe:: len(list)
+
+ The length of the list.
+
+ It also supports the append() method from :class:`list`:
+
+ .. method:: append(pkg: Package)
+
+ Append a new package to the end of the list. Please note that
+ you may not append a package twice, as only as much packages
+ as in the cache can be added.
+
+ The class also defines several specific attributes and methods,
+ to be described hereinafter.
+
+ .. method:: score(pkg: Package)
+
+ Return the score of the package. Packages are basically
+ ordered by descending score.
+
+ This class allows flags to be set on packages. Those flags are:
+
+ .. attribute:: FLAG_ADDED
+ .. attribute:: FLAG_ADD_PENDING
+ .. attribute:: FLAG_IMMEDIATE
+ .. attribute:: FLAG_LOOP
+ .. attribute:: FLAG_UNPACKED
+ .. attribute:: FLAG_CONFIGURED
+ .. attribute:: FLAG_REMOVED
+ .. attribute:: FLAG_STATES_MASK
+
+ Same as ``FLAG_UNPACKED | FLAG_CONFIGURED | FLAG_REMOVED``
+
+ .. attribute:: FLAG_IN_LIST
+ .. attribute:: FLAG_AFTER
+
+ The methods to work with those flags are:
+
+ .. method:: flag(pkg: Package, flag: int[, unset_flags: int])
+
+ Flag a package. Sets the flags given in *flag* and unsets
+ any flags given in *unset_flags*.
+
+ .. method:: is_flag(pkg: Package, flag: int)
+
+ Check whether the flags in *flag* are set for the package.
+
+ .. method:: wipe_flags(flags: int)
+
+ Remove the flags in *flags* from all packages.
+
+ .. method:: is_missing(pkg: Package)
+
+ Check if the package is missing (not really usable right now)
+
+ .. method:: is_now(pkg: Package)
+
+ Check if the package is flagged for any state but removal.
+
+ The following methods for ordering are provided:
+
+ .. method:: order_critical()
+
+ Order the packages for critical unpacking; that is, only
+ respect pre-dependencies.
+
+ .. method:: order_unpack()
+
+ Order the packages for unpacking, repecting Pre-Depends and
+ Conflicts.
+
+ .. method:: order_configure()
+
+ Order the packages for configuration, respecting Depends.
+
+Improve performance with :class:`ActionGroup`
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. class:: ActionGroup(depcache)
+
+ Create a new :class:`ActionGroup()` object for the :class:`DepCache` object
+ given by the parameter *depcache*.
+
+ :class:`ActionGroup()` objects make operations on the cache faster by
+ delaying certain cleanup operations until the action group is released.
+
+ An action group is also a context manager and therefore supports the
+ :keyword:`with` statement. But because it becomes active as soon as it
+ is created, you should not create an ActionGroup() object before entering
+ the with statement. Thus, you should always use the following form::
+
+ with apt_pkg.ActionGroup(depcache):
+ ...
+
+ For code which has to run on Python versions prior to 2.5, you can also
+ use the traditional way::
+
+ actiongroup = apt_pkg.ActionGroup(depcache)
+ ...
+ actiongroup.release()
+
+ In addition to the methods required to implement the context
+ manager interface, :class:`ActionGroup` objects provide the
+ following method:
+
+ .. method:: release()
+
+ Release the ActionGroup. This will reactive the collection of package
+ garbage.
+
+Resolving Dependencies with :class:`ProblemResolver`
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. class:: ProblemResolver(depcache: DepCache)
+
+ ProblemResolver objects take care of resolving problems with
+ dependencies. They mark packages for installation/removal and
+ try to satisfy all dependencies. The constructor takes a single
+ argument of the type :class:`apt_pkg.DepCache` to determine the
+ cache that shall be manipulated in order to resolve the problems.
+
+ .. method:: clear(pkg: Package)
+
+ Revert the action of calling :meth:`protect` or :meth:`remove` on
+ a package, resetting it to the default state.
+
+ .. method:: install_protect()
+
+ Mark all protected packages for installation.
+
+ .. method:: protect(pkg: Package)
+
+ Mark the package given by *pkg* as protected; that is, its state
+ will not be changed.
+
+ .. method:: remove(pkg: Package)
+
+ Mark the package given by *pkg* for removal in the resolver.
+
+ .. method:: resolve([fix_broken: bool = True]) -> bool
+
+ Try to intelligently resolve problems by installing and removing
+ packages. If *fix_broken* is ``True``, apt will try to repair broken
+ dependencies of installed packages.
+
+ .. method:: resolve_by_keep() -> bool
+
+ Try to resolve the problems without installing or removing packages.
+
+ .. method:: keep_phased_updates() -> bool
+
+ Hold back upgrades to phased versions of already installed
+ packages, unless they are security updates.
+
+:class:`Group` of packages with the same name
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. class:: Group(cache: Cache, name: str)
+
+ .. versionadded:: 0.8.0
+
+ A collection of packages in which all packages have the same name. Groups
+ are used in multi-arch environments, where two or more packages have the
+ same name, but different architectures.
+
+ Group objects provide the following parts for sequential access:
+
+ .. describe:: group[index]
+
+ Get the package at the given **index** in the group.
+
+ .. note::
+ Groups are internally implemented using a linked list. The object
+ keeps a pointer to the current object and the first object, so
+ access to the first element, or accesses in order have a
+ complexity of O(1). Random-access complexity is ranges from
+ O(1) to O(n).
+
+ Group objects also provide special methods to find single packages:
+
+ .. method:: find_package(architecture: str) -> Package
+
+ Find a package with the groups name and the architecture given
+ in the argument *architecture*. If no such package exists, return
+ ``None``.
+
+ .. method:: find_preferred_package(prefer_nonvirtual: bool = True) -> Package
+
+ Find the preferred package. This is the package of the native
+ architecture (specified in ``APT::Architecture``) if available,
+ or the package from the first foreign architecture. If no package
+ could be found, return ``None``
+
+ If **prefer_nonvirtual** is ``True``, the preferred package
+ will be a non-virtual package, if one exists.
+
+
+:class:`Package` information
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. class:: Package
+
+ Represent a package. A package is uniquely identified by its name and
+ architecture and each package can have zero or more versions which can be
+ accessed via the :attr:`version_list` property. Packages can be
+ installed and removed by a :class:`DepCache` object.
+
+ Attributes:
+
+ .. attribute: architecture
+
+ The architecture of the package. This is relevant on multi-arch
+ systems only. Please note that if a package is Architecture: all,
+ this value is not "all", but the architecture of the package file
+ it comes from.
+
+ .. versionadded:: 0.7.100.3
+
+ .. attribute:: current_ver
+
+ The version currently installed as a :class:`Version` object, or None
+ if the package is not installed.
+
+ .. method:: get_fullname([pretty: bool = False]) -> str
+
+ Get the full name of the package, including the architecture. If
+ *pretty* is ``True``, the architecture is omitted for native packages,
+ that is, an amd64 "apt" package on an amd64 system would give "apt".
+
+ .. versionadded:: 0.7.100.3
+
+ .. attribute:: has_provides
+
+ A boolean value determining whether the list available via the
+ attribute :attr:`provides_list` has at least one element. This
+ value may be used in combination with :attr:`has_versions` to
+ check whether a package is virtual; that is, it has no versions
+ and is provided at least once::
+
+ pkg.has_provides and not pkg.has_versions
+
+ .. attribute:: has_versions
+
+ A boolean value determining whether the list available via the
+ attribute :attr:`version_list` has at least one element. This
+ value may be used in combination with :attr:`has_provides` to
+ check whether a package is virtual; that is, it has no versions
+ and is provided at least once::
+
+ pkg.has_provides and not pkg.has_versions
+
+ .. attribute:: id
+
+ The ID of the package. This can be used to store information about
+ the package. The ID is an int value.
+
+ .. attribute:: name
+
+ This is the name of the package.
+
+ .. attribute:: provides_list
+
+ A list of all package versions providing this package. Each element
+ of the list is a triplet, where the first element is the name of the
+ provided package, the second element the provided version (empty
+ string), and the third element the version providing this package
+ as a :class:`Version` object.
+
+ .. attribute:: rev_depends_list
+
+ An iterator of :class:`Dependency` objects for dependencies on this
+ package. The returned iterator is implemented by the class
+ :class:`DependencyList`:
+
+ .. class:: DependencyList
+
+ A simple list-like type for representing multiple dependency
+ objects in an efficient manner; without having to generate
+ all Dependency objects in advance.
+
+ .. describe:: list[index]
+
+ Return the item at the position *index* in the list.
+
+ .. method:: __len__()
+
+ The length of the list. This method should not be used
+ irectly, instead Python's built-in function :func:`len`
+ should be used.
+
+ .. attribute:: section
+
+ The section of the package, as specified in the record. The list of
+ possible sections is defined in the Policy. This is a string.
+
+ .. deprecated:: 1.0
+
+ A package can have multiple versions with different sections, so
+ the section information should be accessed from the version class.
+
+ .. attribute:: version_list
+
+ A list of :class:`Version` objects for all versions of this package
+ available in the cache.
+
+ **States**:
+
+ .. attribute:: selected_state
+
+ The state we want it to be, ie. if you mark a package for installation,
+ this is :attr:`apt_pkg.SELSTATE_INSTALL`.
+
+ See :ref:`SelStates` for a list of available states.
+
+ .. attribute:: inst_state
+
+ The state the currently installed version is in. This is normally
+ :attr:`apt_pkg.INSTSTATE_OK`, unless the installation failed.
+
+ See :ref:`InstStates` for a list of available states.
+
+ .. attribute:: current_state
+
+ The current state of the package (not installed, unpacked, installed,
+ etc). See :ref:`CurStates` for a list of available states.
+
+ **Flags**:
+
+ .. attribute:: essential
+
+ Whether the package has the 'Essential' flag set; that is,
+ whether it has a field 'Essential: yes' in its record.
+
+ .. attribute:: important
+
+ Whether the package has the (obsolete) 'Important' flag set; that is,
+ whether it has a field 'Important: yes' in its record.
+
+Example:
+~~~~~~~~~
+.. literalinclude:: ../examples/cache-packages.py
+
+
+
+:class:`Version`
+^^^^^^^^^^^^^^^^^
+.. class:: Version
+
+ The version object contains all information related to a specific package
+ version.
+
+ .. attribute:: arch
+
+ The architecture of the package, eg. amd64 or all.
+
+ .. attribute:: depends_list
+
+ This is basically the same as :attr:`depends_list_str`,
+ but instead of the ('pkgname', 'version', 'relation') tuples,
+ it returns :class:`Dependency` objects, which can assist you with
+ useful functions.
+
+ .. attribute:: depends_list_str
+
+ A dictionary of dependencies. The key specifies the type of the
+ dependency ('Depends', 'Recommends', etc.).
+
+ The value is a list, containing items which refer to the or-groups of
+ dependencies. Each of these or-groups is itself a list, containing
+ tuples like ('pkgname', 'version', 'relation') for each or-choice.
+
+ An example return value for a package with a 'Depends: python (>= 2.4)'
+ would be::
+
+ {'Depends': [
+ [
+ ('python', '2.4', '>=')
+ ]
+ ]
+ }
+
+ The same for a dependency on A (>= 1) | B (>= 2)::
+
+ {'Depends': [
+ [
+ ('A', '1', '>='),
+ ('B', '2', '>='),
+ ]
+ ]
+ }
+
+ The comparison operators are not the Debian ones, but the standard
+ comparison operators as used in languages such as C and Python. This
+ means that '>' means "larger than" and '<' means "less than".
+
+ .. attribute:: downloadable
+
+ Whether this package can be downloaded from a remote site.
+
+ .. attribute:: file_list
+
+ A list of (:class:`PackageFile`, int: index) tuples for all Package
+ files containing this version of the package.
+
+ .. attribute:: hash
+
+ An integer hash value used for the internal storage.
+
+ .. attribute:: id
+
+ A numeric identifier which uniquely identifies this version in all
+ versions in the cache.
+
+ .. attribute:: installed_size
+
+ The size of the package (in kilobytes), when unpacked on the disk.
+
+ .. attribute:: multi_arch
+
+ The multi-arch state of the package. Can be one of the following
+ attributes.
+
+ .. attribute:: MULTI_ARCH_NO
+
+ No multi-arch
+
+ .. attribute:: MULTI_ARCH_ALL
+
+ An ``Architecture: all`` package
+
+
+ .. attribute:: MULTI_ARCH_FOREIGN
+
+ Can satisfy dependencies of foreign-architecture
+ packages
+
+ .. attribute:: MULTI_ARCH_ALL_FOREIGN
+
+ :attr:`MULTI_ARCH_FOREIGN` for ``Architecture: all``
+ packages.
+
+ .. attribute:: MULTI_ARCH_SAME
+
+ Multiple versions from different architectures may be
+ installed in parallel, but may only satisfy dependencies
+ of packages from the same architecture
+
+ .. attribute:: MULTI_ARCH_ALLOWED
+
+ Installation in parallel and satisfying ``pkg:any``
+ style dependencies is allowed.
+
+ .. attribute:: MULTI_ARCH_ALL_ALLOWED
+
+ :attr:`MULTI_ARCH_ALLOWED` for ``Architecture: all``
+ packages.
+
+
+
+
+ .. attribute:: parent_pkg
+
+ The :class:`Package` object this version belongs to.
+
+ .. attribute:: priority
+
+ The integer representation of the priority. This can be used to speed
+ up comparisons a lot, compared to :attr:`priority_str`.
+
+ The values are defined in the :mod:`apt_pkg` extension, see
+ :ref:`Priorities` for more information.
+
+ .. attribute:: priority_str
+
+ Return the priority of the package version, as a string, eg.
+ "optional".
+
+ .. attribute:: provides_list
+
+ This returns a list of all packages provided by this version. Like
+ :attr:`Package.provides_list`, it returns a list of tuples
+ of the form ('virtualpkgname', '', :class:`Version`), where as the
+ last item is the same as the object itself.
+
+ .. attribute:: section
+
+ The usual sections (eg. admin, net, etc.). Prefixed with the component
+ name for packages not in main (eg. non-free/admin).
+
+ .. attribute:: size
+
+ The size of the .deb file, in bytes.
+
+ .. attribute:: translated_description
+
+ Return a :class:`Description` object for the translated description
+ of this package version.
+
+ .. attribute:: is_security_update
+
+ Whether this version is a security update.
+
+ .. attribute:: ver_str
+
+ The version, as a string.
+
+
+
+:class:`Dependency`
+^^^^^^^^^^^^^^^^^^^^
+.. class:: Dependency
+
+ Represent a dependency from one package to another one.
+
+ .. method:: all_targets
+
+ A list of all possible target :class:`Version` objects which satisfy
+ this dependency.
+
+ .. attribute:: comp_type
+
+ The type of comparison (<,<=,=,!=,>=,>,), as string. Note that the
+ empty string is a valid string as well, if no version is specified.
+
+ .. attribute:: dep_type
+
+ The type of the dependency, as string, eg. "Depends".
+
+ .. attribute:: dep_type_enum
+
+ The type of the dependency, as an integer which can be compared to
+ one of the TYPE_* constants below.
+
+ .. attribute:: dep_type_untranslated
+
+ The type of the depndency, as an untranslated string.
+
+ .. attribute:: id
+
+ The ID of the package, as integer.
+
+ .. attribute:: parent_pkg
+
+ The :class:`Package` object of the package which declares the
+ dependency. This is the same as using ParentVer.ParentPkg.
+
+ .. attribute:: parent_ver
+
+ The :class:`Version` object of the parent version, ie. the package
+ which declares the dependency.
+
+ .. attribute:: target_pkg
+
+ The :class:`Package` object of the target package.
+
+ .. attribute:: target_ver
+
+ The target version of the dependency, as string. Empty string if the
+ dependency is not versioned.
+
+ The following constants describe all values the attribute *dep_type_enum*
+ can take:
+
+ .. attribute:: TYPE_CONFLICTS
+
+ Constant for checking against dep_type_enum
+
+ .. attribute:: TYPE_DEPENDS
+
+ Constant for checking against dep_type_enum
+
+ .. attribute:: TYPE_DPKG_BREAKS
+
+ Constant for checking against dep_type_enum
+
+ .. attribute:: TYPE_ENHANCES
+
+ Constant for checking against dep_type_enum
+
+ .. attribute:: TYPE_OBSOLETES
+
+ Constant for checking against dep_type_enum
+
+ .. attribute:: TYPE_PREDEPENDS
+
+ Constant for checking against dep_type_enum
+
+ .. attribute:: TYPE_RECOMMENDS
+
+ Constant for checking against dep_type_enum
+
+ .. attribute:: TYPE_REPLACES
+
+ Constant for checking against dep_type_enum
+
+ .. attribute:: TYPE_SUGGESTS
+
+ Constant for checking against dep_type_enum
+
+Example: Find all missing dependencies
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+With the help of Dependency.all_targets(), you can easily find all packages with
+broken dependencies:
+
+.. literalinclude:: ../examples/missing-deps.py
+
+
+:class:`Description`
+^^^^^^^^^^^^^^^^^^^^^
+.. class:: Description
+
+ Represent the description of the package.
+
+ .. attribute:: language_code
+
+ The language code of the description; or, if the description
+ is untranslated, an empty string.
+
+ .. attribute:: md5
+
+ The MD5 checksum of the description.
+
+ .. attribute:: file_list
+
+ A list of tuples ``(packagefile: PackageFile, index: int)``.
+
+Package Pinning with :class:`Policy`
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+.. class:: Policy(cache: apt_pkg.Cache)
+
+ Representation of the policy of the :class:`Cache` object given by
+ *cache*. This provides a superset of policy-related functionality
+ compared to the *DepCache* class. The DepCache can be used for most
+ purposes, but there may be some cases where a special policy class
+ is needed.
+
+ .. method:: create_pin(type: str, pkg: str, data: str, priority: int)
+
+ Create a pin for the policy. The parameter *type* refers to one of the
+ strings 'Version', 'Release', or 'Origin'. The argument *pkg* is the
+ name of the package. The parameter *data* refers to the value (such
+ as 'unstable' for type='Release') and the other possible options.
+ The parameter 'priority' gives the priority of the pin.
+
+ .. automethod:: init_defaults
+
+ .. method:: get_candidate_ver(package: apt_pkg.Package) -> apt_pkg.Version
+
+ Get the best package for the job; that is, the package with the
+ highest pin priority.
+
+ .. method:: get_priority(package: Union[apt_pkg.Version, apt_pkg.PackageFile]) -> int
+
+ Get the pin priority of the package, version, or package file
+ given by *package*.
+
+ .. versionchanged:: 1.7
+
+ Introduce support for per-version pins. Deprecated support
+ for :class:`apt_pkg.Package`.
+
+ .. method:: read_pindir(dirname: str) -> bool
+
+ Read the pin files in the given dir (e.g. '/etc/apt/preferences.d')
+ and add them to the policy.
+
+ .. method:: read_pinfile(filename: str) -> bool
+
+ Read the pin file given by *filename* (e.g. '/etc/apt/preferences')
+ and add it to the policy.
+
+
+Index Files
+-------------
+
+.. class:: MetaIndex
+
+ Represent a Release file as stored in the cache.
+
+ .. attribute:: uri
+
+ The URI the meta index file is located at, as a string.
+
+ .. attribute:: dist
+
+ The distribution stored in the meta index, as a string.
+
+ .. attribute:: is_trusted
+
+ A boolean value determining whether the meta index can be trusted. This
+ is ``True`` for signed Release files.
+
+ .. attribute:: index_files
+
+ A list of all :class:`IndexFile` objects associated with this meta
+ index.
+
+
+.. class:: IndexFile
+
+ Represent an index file, that is, package indexes, translation indexes,
+ and source indexes.
+
+ .. method:: archive_uri(path: str) -> str
+
+ Return the URI to the given path in the archive.
+
+ .. attribute:: label
+
+ The label of the index file.
+
+ .. attribute:: describe
+
+ A string describing this object.
+
+ .. attribute:: exists
+
+ A boolean value determining whether the index file exists.
+
+ .. attribute:: has_packages
+
+ A boolean value determining whether the index file has packages.
+
+ .. attribute:: size
+
+ The size of the file, measured in bytes.
+
+ .. attribute:: is_trusted
+
+ A boolean value determining whether the file can be trusted; that is,
+ because it is from a source with a GPG signed Release file.
+
+
+
+.. class:: PackageFile
+
+ Provide access to an index file stored in the cache, such as
+ :file:`/var/lib/dpkg/status`.
+
+ .. attribute:: architecture
+
+ The architecture of the package file. This attribute normally
+ contains an empty string and is thus not very useful.
+
+ .. attribute:: archive
+
+ The archive of the package file as set in the Release file via
+ the "Suite" field. If there is no Release file, this is an empty
+ string.
+
+ .. attribute:: component
+
+ The component of the package file, if it is provided by a repository
+ using the dists/ hierarchy. For other packages files, this property
+ is an empty string.
+
+ .. attribute:: filename
+
+ The path to the file on the local filesystem.
+
+ .. attribute:: id
+
+ The ID of the package. This is an integer which can be used to store
+ further information about the file [eg. as dictionary key].
+
+ .. attribute:: index_type
+
+ A string describing the type of index. Known values are
+ "Debian Package Index", "Debian Translation Index", and
+ "Debian dpkg status file".
+
+ .. attribute:: label
+
+ The label of the package file as set in the release file
+ via the 'Label' field. If there is no Release file, this
+ attribute is an empty string.
+
+ .. attribute:: not_automatic
+
+ Whether packages from this list will be updated automatically. The
+ default for example is False.
+
+ .. attribute:: not_source
+
+ Whether the file has no source from which it can be updated. In such a
+ case, the value is ``True``; else ``False``. For example, it is
+ ``False`` for :file:`/var/lib/dpkg/status`.
+
+ Example::
+
+ for pkgfile in cache.file_list:
+ if pkgfile.not_source:
+ print('The file %s has no source.' % pkgfile.filename)
+
+ .. attribute:: origin
+
+ The Origin, as set in the Release file
+
+ .. attribute:: site
+
+ The hostname of the site.
+
+ .. attribute:: size
+
+ The size of the file.
+
+ .. attribute:: version
+
+ The version, as set in the release file (eg. "4.0" for "Etch")
+
+
+The following example shows how to use PackageFile:
+
+.. literalinclude:: ../examples/cache-pkgfile.py
+
+
+Records (Release files, Packages, Sources)
+------------------------------------------
+
+.. class:: IndexRecords()
+
+ Represent a Release file and provide means to read information from
+ the file. This class provides several methods:
+
+ .. method:: get_dist() -> str
+
+ Return the distribution set in the Release file.
+
+ .. method:: load(filename: str)
+
+ Load the file located at the path given by *filename*.
+
+ .. method:: lookup(key: str) -> (HashString, int)
+
+ Look up the filename given by *key* and return a tuple (hash, size),
+ where the first element *hash* is a :class:`HashString` object
+ and the second element *size* is an int object.
+
+
+.. class:: PackageRecords(cache: apt_pkg.Cache)
+
+ Provide further information about the packages in the :class:`Cache` object
+ *cache*. This efficiently parses the package files to provide information
+ not available in the cache, such as maintainer, hash sums, description,
+ and the file name of the package. It also provides the complete record
+ of the package.
+
+ .. method:: lookup(verfile_iter: (PackageFile, int)) -> bool
+
+ Change the actual package to the package given by the verfile_iter.
+
+ The parameter *verfile_iter* refers to a tuple consisting
+ of (:class:`PackageFile()`, int: index), as returned by various
+ ``file_list`` attributes such as :attr:`Version.file_list`.
+
+ Example (shortened)::
+
+ cand = depcache.get_candidate_ver(cache['python-apt'])
+ records.lookup(cand.file_list[0])
+ # Now you can access the record
+ print(records.source_pkg) # == python-apt
+
+ .. describe:: section[key]
+
+ Return the value of the field at *key*. If *key* is not available,
+ raise :exc:`KeyError`.
+ Raises AttributeError if not yet looked up.
+
+ .. versionadded:: 1.7
+
+ .. describe:: key in section
+
+ Return ``True`` if *section* has a key *key*, else ``False``.
+ Raises AttributeError if not yet looked up.
+
+ .. versionadded:: 1.7
+
+ .. attribute:: filename
+
+ Return the field 'Filename' of the record. This is the path to the
+ package, relative to the base path of the archive.
+
+ .. attribute:: hashes
+
+ A :class:`apt_pkg.HashStringList` of all hashes.
+
+ .. versionadded:: 1.1
+
+ .. attribute:: md5_hash
+
+ Return the MD5 hashsum of the package This refers to the field
+ 'MD5Sum' in the raw record.
+
+ .. deprecated:: 1.1
+
+ Use :attr:`hashes` instead.
+
+ .. attribute:: sha1_hash
+
+ Return the SHA1 hashsum of the package. This refers to the field 'SHA1'
+ in the raw record.
+
+ .. deprecated:: 1.1
+
+ Use :attr:`hashes` instead.
+
+ .. attribute:: sha256_hash
+
+ Return the SHA256 hashsum of the package. This refers to the field
+ 'SHA256' in the raw record.
+
+ .. versionadded:: 0.7.9
+
+ .. deprecated:: 1.1
+
+ Use :attr:`hashes` instead.
+
+ .. attribute:: source_pkg
+
+ The name of the source package, if different from the name of the
+ binary package. This information is retrieved from the 'Source' field.
+
+ .. attribute:: source_ver
+
+ The version of the source package, if it differs from the version
+ of the binary package. Just like 'source_pkg', this information
+ is retrieved from the 'Source' field.
+
+ .. attribute:: maintainer
+
+ Return the maintainer of the package.
+
+ .. attribute:: short_desc
+
+ Return the short description. This is the summary on the first line of
+ the 'Description' field.
+
+ .. attribute:: long_desc
+
+ Return the long description. These are lines 2-END from the
+ 'Description' field.
+
+ .. attribute:: name
+
+ Return the name of the package. This is the 'Package' field.
+
+ .. attribute:: homepage
+
+ Return the Homepage. This is the 'Homepage' field.
+
+ .. attribute:: record
+
+ Return the whole record as a string. If you want to access fields of
+ the record not available as an attribute, you can use
+ :class:`apt_pkg.TagSection` to parse the record and access the field
+ name.
+
+ .. deprecated:: 1.7
+
+ This property can be considered deprecated for simple string
+ lookups, as keys can now be looked up in the record itself.
+
+ Example::
+
+ section = apt_pkg.TagSection(records.record)
+ print(section['SHA256']) # Use records.sha256_hash instead
+
+.. class:: SourceRecords
+
+ Provide an easy way to look up the records of source packages and
+ provide easy attributes for some widely used fields of the record.
+
+ .. note::
+
+ If the Lookup failed, because no package could be found, no error is
+ raised. Instead, the attributes listed below are simply not existing
+ anymore (same applies when no Lookup has been made, or when it has
+ been restarted).
+
+ .. method:: lookup(pkgname: str) -> bool
+
+ Look up the source package with the given name. Each call moves
+ the position of the records parser forward. If there are no
+ more records, return None. If the lookup failed this way,
+ access to any of the attributes will result in an
+ :exc:`AttributeError`.
+
+ Imagine a package P with two versions X, Y. The first ``lookup(P)``
+ would set the record to version X and the second ``lookup(P)`` to
+ version Y. A third call would return ``None`` and access to any
+ of the below attributes will result in an :exc:`AttributeError`
+
+ .. method:: restart()
+
+ Restart the lookup process. This moves the parser to the first
+ package and lookups can now be made just like on a new object.
+
+ Imagine a package P with two versions X, Y. The first ``Lookup(P)``
+ would set the record to version X and the second ``Lookup(P)`` to
+ version Y. If you now call ``restart()``, the internal position
+ will be cleared. Now you can call ``lookup(P)`` again to move to X.
+
+ .. attribute:: binaries
+
+ Return a list of strings describing the package names of the binaries
+ created by the source package. This matches the 'Binary' field in the
+ raw record.
+
+ .. attribute:: build_depends
+
+ Return a dictionary representing the build-time dependencies of the
+ package. The format is the same as for :attr:`Version.depends_list_str`
+ and possible keys being ``"Build-Depends"``, ``"Build-Depends-Indep"``,
+ ``"Build-Conflicts"`` or ``"Build-Conflicts-Indep"``.
+
+ .. attribute:: files
+
+ The list of files. This returns a list of :class:`SourceRecordsFile`
+
+ .. versionchanged:: 1.6
+
+ Used to be a list of tuples, see :class:`SourceRecordFile` for the tuple
+ layout.
+
+ .. attribute:: index
+
+ A list of :class:`IndexFile` objects associated with this
+ source package record.
+
+ .. attribute:: maintainer
+
+ A string describing the name of the maintainer.
+
+ .. attribute:: package
+
+ The name of the source package.
+
+ .. attribute:: record
+
+ The whole record, as a string. You can use :func:`apt_pkg.ParseSection`
+ if you need to parse it. You need to parse the record to access
+ fields not available via the attributes such as 'Standards-Version'
+
+ .. attribute:: section
+
+ A string describing the section.
+
+ .. attribute:: version
+
+ A string describing the version of the source package.
+
+.. class:: SourceRecordsFile
+
+ Represents a file in a source record.
+
+ .. versionadded:: 1.6
+
+ Before 1.6, this was a tuple `(md5, size, path, type)`.
+
+ .. attribute:: hashes
+
+ A :class:`HashStringList` of the file's hashes.
+
+ .. attribute:: path
+
+ The path to the file
+
+ .. attribute:: size
+
+ The size of the file
+
+ .. attribute:: type
+
+ The type of the file. Can be 'diff' (includes .debian.tar.gz), 'dsc', or 'tar'.
+
+The Acquire interface
+----------------------
+The Acquire Interface is responsible for all sorts of downloading in apt. All
+packages, index files, etc. downloading is done using the Acquire functionality.
+
+The :mod:`apt_pkg` module provides a subset of this functionality which allows
+you to implement file downloading in your applications. Together with the
+:class:`PackageManager` class you can also fetch all the packages marked for
+installation.
+
+.. class:: Acquire([progress: apt.progress.base.AcquireProgress])
+
+ Coordinate the retrieval of files via network or local file system
+ (using ``copy://path/to/file`` style URIs). Items can be added to
+ an Acquire object using various means such as creating instances
+ of :class:`AcquireFile` or the methods :meth:`SourceList.get_indexes`
+ and :meth:`PackageManager.get_archives`.
+
+ Acquire objects maintain a list of items which will be fetched or have
+ been fetched already during the lifetime of this object. To add new items
+ to this list, you can create new :class:`AcquireFile` objects which allow
+ you to add single files.
+
+ The constructor takes an optional parameter *progress* which takes an
+ :class:`apt.progress.base.AcquireProgress` object. This object may then
+ report progress information (see :mod:`apt.progress.text` for reporting
+ progress to a I/O stream).
+
+ Acquire items have two methods to start and stop the fetching:
+
+ .. method:: run() -> int
+
+ Fetch all the items which have been added by :class:`AcquireFile` and
+ return one of the constants :attr:`RESULT_CANCELLED`,
+ :attr:`RESULT_CONTINUE`, :attr:`RESULT_FAILED` to describe the
+ result of the run.
+
+ .. method:: shutdown()
+
+ Shut the fetcher down. This removes all items from the queue and
+ makes all :class:`AcquireItem`, :class:`AcquireWorker`,
+ :class:`AcquireItemDesc` objects useless. Accessing an object of one
+ of those types can cause a segfault then.
+
+ Removing an item does not mean that the already fetched data will
+ be removed from the destination. Instead, APT might use the partial
+ result and continue from thereon.
+
+ Furthermore, they provide three attributes which provide information
+ on how much data is already available and how much data still needs
+ to be fetched:
+
+ .. attribute:: fetch_needed
+
+ The amount of data that has to be fetched in order to fetch all
+ queued items.
+
+ .. attribute:: partial_present
+
+ The amount of data which is already available.
+
+ .. attribute:: total_needed
+
+ The total amount of bytes needed (including those of files which are
+ already present).
+
+ They also provide two attributes representing the items being processed
+ and the workers fetching them:
+
+ .. attribute:: items
+
+ A list of :class:`AcquireItem` objects which are attached to the
+ to this Acquire object. This includes all items ever attached to
+ this object (except if they were removed using, for example,
+ :meth:`shutdown()` or by deleting an :class:`AcquireFile` object.)
+
+ .. attribute:: workers
+
+ A list of :class:`AcquireWorker` objects which are currently active
+ on this instance.
+
+ The Acquire class comes with three constants which represents the results
+ of the :meth:`run` method:
+
+ .. attribute:: RESULT_CANCELLED
+
+ The fetching has been aborted, e.g. due to a progress class returning
+ ``False`` in its :meth:`pulse()` method.
+
+ .. attribute:: RESULT_CONTINUE
+
+ All items have been fetched successfully or failed transiently
+ and the process has not been canceled.
+
+ You need to look at the status of each item and check if it has not
+ failed transiently to discover errors like a Not Found when acquiring
+ packages.
+
+ .. attribute:: RESULT_FAILED
+
+ An item failed to fetch due to some reasons.
+
+
+.. class:: AcquireItem
+
+ An AcquireItem object represents a single item of an :class:`Acquire`
+ object. It is an abstract class to represent various types of items
+ which are implemented as subclasses. The only exported subclass is
+ :class:`AcquireFile` which can be used to fetch files.
+
+ .. attribute:: complete
+
+ A boolean value which is True only if the item has been
+ fetched successfully.
+
+ .. attribute:: desc_uri
+
+ An URI describing where the item is located at.
+
+ .. attribute:: destfile
+
+ The path to the local location where the fetched data will be
+ stored at.
+
+ .. attribute:: error_text
+
+ The error message. For example, when a file does not exist on a HTTP
+ server, this will contain a 404 error message.
+
+ .. attribute:: filesize
+
+ The size of the file, in bytes. If the size of the to be fetched file
+ is unknown, this attribute is set to ``0``.
+
+ .. attribute:: id
+
+ The ID of the item. This attribute is normally set to ``0``, users may
+ set a custom value here, for instance in an overridden
+ :meth:`apt.progress.base.AcquireProgress.fetch` method (the progress
+ class could keep a counter, increase it by one for every :meth:`fetch`
+ call and assign the current value to this attribute).
+
+ .. attribute:: is_trusted
+
+ A boolean value determining whether the file is trusted. Only ``True``
+ if the item represents a package coming from a repository which is
+ signed by one of the keys in APT's keyring.
+
+ .. attribute:: local
+
+ A boolean value determining whether this file is locally available
+ (``True``) or whether it has to be fetched from a remote source
+ (``False``).
+
+ .. attribute:: mode
+
+ Old name for active_subprocess
+
+ .. deprecated:: 1.0
+
+ .. attribute:: active_subprocess
+
+ The name of the active subprocess (for instance, 'gzip', 'rred' or 'gpgv').
+
+ .. versionadded:: 1.0
+
+ **Status**:
+
+ The following attribute represents the status of the item. This class
+ provides several constants for comparing against this value which are
+ listed here as well.
+
+ .. attribute:: status
+
+ Integer, representing the status of the item. This attribute can be
+ compared against the following constants to gain useful information
+ on the item's status.
+
+ .. attribute:: STAT_AUTH_ERROR
+
+ An authentication error occurred while trying to fetch the item.
+
+ .. attribute:: STAT_DONE
+
+ The item is completely fetched and there have been no problems
+ while fetching the item.
+
+ .. attribute:: STAT_ERROR
+
+ An error occurred while trying to fetch the item. This error is
+ normally not related to authentication problems, as thus are
+ dealt with using :attr:`STAT_AUTH_ERROR`.
+
+ .. attribute:: STAT_FETCHING
+
+ The item is being fetched currently.
+
+ .. attribute:: STAT_IDLE
+
+ The item is yet to be fetched.
+
+ .. attribute:: STAT_TRANSIENT_NETWORK_ERROR
+
+ There was a network error.
+
+
+.. class:: AcquireFile(owner, uri[, hash, size, descr, short_descr, destdir, destfile])
+
+ Create a new :class:`AcquireFile()` object and register it with *acquire*,
+ so it will be fetched. You must always keep around a reference to the
+ object, otherwise it will be removed from the Acquire queue again.
+
+ The parameter *owner* refers to an :class:`Acquire()` object as returned
+ by :func:`GetAcquire`. The file will be added to the Acquire queue
+ automatically.
+
+ The parameter *uri* refers to the location of the file, any protocol
+ of apt is supported.
+
+ The parameter *hash* refers to the hash of the file. If this is set
+ libapt will check the file after downloading. This should be an instance
+ of :class:`apt_pkg.HashStringList`.
+
+ The parameter *size* can be used to specify the size of the package,
+ which can then be used to calculate the progress and validate the download.
+
+ The parameter *descr* is a description of the download. It may be
+ used to describe the item in the progress class. *short_descr* is the
+ short form of it.
+
+ The parameters *descr* and *short_descr* can be used to specify
+ descriptions for the item. The string passed to *descr* should
+ describe the file and its origin (e.g. "http://localhost sid/main
+ python-apt 0.7.94.2") and the string passed to *short_descr* should
+ be one word such as the name of a package.
+
+ Normally, the file will be stored in the current directory using the
+ file name given in the URI. This directory can be changed by passing
+ the name of a directory to the *destdir* parameter. It is also possible
+ to set a path to a file using the *destfile* parameter, but both can
+ not be specified together.
+
+ In terms of attributes, this class is a subclass of :class:`AcquireItem`
+ and thus inherits all its attributes.
+
+ .. versionchanged:: 1.9.1
+
+ The *hash* parameter now accepts an :class:`apt_pkg.HashStringList`,
+ the old *md5* parameter has been removed.
+
+.. class:: AcquireWorker
+
+ An :class:`AcquireWorker` object represents a sub-process responsible for
+ fetching files from remote locations. There is no possibility to create
+ instances of this class from within Python, but a list of objects of
+ currently active workers is provided by :attr:`Acquire.workers`.
+
+ Objects of this type provide several attributes which give information
+ about the worker's current activity.
+
+ .. attribute:: current_item
+
+ The item which is currently being fetched. This returns an
+ :class:`AcquireItemDesc` object.
+
+ .. attribute:: current_size
+
+ How many bytes of the file have been downloaded. Zero if the current
+ progress of the file cannot be determined.
+
+ .. attribute:: resumepoint
+
+ The amount of data which was already available when the download was
+ started.
+
+ .. attribute:: status
+
+ The most recent (localized) status string received from the
+ sub-process.
+
+ .. attribute:: total_size
+
+ The total number of bytes to be downloaded for the item. Zero if the
+ total size is unknown.
+
+.. class:: AcquireItemDesc
+
+ An :class:`AcquireItemDesc` object stores information about the item which
+ can be used to describe the item. Objects of this class are used in the
+ progress classes, see the :class:`apt.progress.base.AcquireProgress`
+ documentation for information how.
+
+ .. attribute:: description
+
+ The long description given to the item.
+
+ .. attribute:: owner
+
+ The :class:`AcquireItem` object owning this object.
+
+ .. attribute:: shortdesc
+
+ A short description which has been given to this item.
+
+ .. attribute:: uri
+
+ The URI from which this item would be downloaded.
+
+
+Hashes
+------
+The apt_pkg module also provides several hash functions. If you develop
+applications with python-apt it is often easier to use these functions instead
+of the ones provides in Python's :mod:`hashlib` module.
+
+The module provides the two classes :class:`Hashes` and :class:`HashString` for
+generic hash support:
+
+.. autoclass:: Hashes
+ :members:
+
+.. class:: HashString(type: str[, hash: str])
+
+ HashString objects store the type of a hash and the corresponding hash.
+ They are used by e.g :meth:`IndexRecords.lookup`. The first parameter,
+ *type* refers to one of "MD5Sum", "SHA1" and "SHA256". The second parameter
+ *hash* is the corresponding hash.
+
+ You can also use a combined form by passing a string with type and hash
+ separated by a colon as the only argument. For example::
+
+ HashString("MD5Sum:d41d8cd98f00b204e9800998ecf8427e")
+
+
+ .. describe:: str(hashstring)
+
+ Convert the HashString to a string by joining the hash type and the
+ hash using ':', e.g. ``"MD5Sum:d41d8cd98f00b204e9800998ecf8427e"``.
+
+ .. attribute:: hashtype
+
+ The type of the hash, as a string. This may be "MD5Sum", "SHA1",
+ "SHA256" or "SHA512".
+
+ .. autoattribute:: hashvalue
+
+ .. autoattribute:: usable
+
+ .. method:: verify_file(filename: str) -> bool
+
+ Verify that the file given by the parameter *filename* matches the
+ hash stored in this object.
+
+.. autoclass:: HashStringList
+ :members:
+
+ .. describe:: len(list)
+
+ Return the length of the list
+
+ .. describe:: list[index]
+
+ Get the :class:`HashString` object at the specified index.
+
+The :mod:`apt_pkg` module also provides the functions :func:`md5sum`,
+:func:`sha1sum` and :func:`sha256sum` for creating a single hash from a
+:class:`bytes` or :class:`file` object:
+
+.. function:: md5sum(object)
+
+ Return the md5sum of the object. *object* may either be a string, in
+ which case the md5sum of the string is returned, or a :class:`file()`
+ object (or a file descriptor), in which case the md5sum of its contents is
+ returned.
+
+ .. versionchanged:: 0.7.100
+ Added support for using file descriptors.
+
+ .. deprecated:: 1.9
+
+ Use :class:`apt_pkg.Hashes` instead. This function will be removed
+ in a later release.
+
+.. function:: sha1sum(object)
+
+ Return the sha1sum of the object. *object* may either be a string, in
+ which case the sha1sum of the string is returned, or a :class:`file()`
+ object (or a file descriptor), in which case the sha1sum of its contents
+ is returned.
+
+ .. versionchanged:: 0.7.100
+ Added support for using file descriptors.
+
+ .. deprecated:: 1.9
+
+ Use :class:`apt_pkg.Hashes` instead. This function will be removed
+ in a later release.
+
+.. function:: sha256sum(object)
+
+ Return the sha256sum of the object. *object* may either be a string, in
+ which case the sha256sum of the string is returned, or a :class:`file()`
+ object (or a file descriptor), in which case the sha256sum of its contents
+ is returned.
+
+ .. versionchanged:: 0.7.100
+ Added support for using file descriptors.
+
+ .. deprecated:: 1.9
+
+ Use :class:`apt_pkg.Hashes` instead. This function will be removed
+ in a later release.
+
+Debian control files
+--------------------
+Debian control files are files containing multiple stanzas of :RFC:`822`-style
+header sections. They are widely used in the Debian community, and can represent
+many kinds of information. One example for such a file is the
+:file:`/var/lib/dpkg/status` file which contains a list of the currently
+installed packages.
+
+The :mod:`apt_pkg` module provides two classes to read those files and parts
+thereof and provides a function :func:`RewriteSection` which takes a
+:class:`TagSection()` object and sorting information and outputs a sorted
+section as a string.
+
+.. class:: TagFile(file, bytes: bool = False)
+
+ An object which represents a typical debian control file. Can be used for
+ Packages, Sources, control, Release, etc.
+
+ The *file* argument shall be a path name or an open file object. The
+ argument *bytes* specifies whether the file shall be represented using
+ bytes (``True``) or unicode (``False``) strings.
+
+ It is a context manager that can be used with a with statement or the
+ :meth:`close` method.
+
+ .. describe:: with TagFile(...) as ...:
+
+ Use the :class:`TagFile` as a context manager. This will automatically
+ close the file after the body finished execution.
+
+ .. versionadded:: 1.0
+
+ .. method:: close()
+
+ Close the file. It's recommended to use the context manager
+ instead (that is, the `with` statement).
+
+ .. versionadded:: 1.0
+
+ It provides two kinds of API which should not be used together:
+
+ The first API implements the iterator protocol and should be used whenever
+ possible because it has less side effects than the other one. It may be
+ used e.g. with a for loop::
+
+ with apt_pkg.TagFile('/var/lib/dpkg/status') as tagfile:
+ for section in tagfile:
+ print(section['Package'])
+
+ .. versionchanged:: 0.7.100
+ Added support for using gzip files, via :class:`gzip.GzipFile` or any
+ file containing a compressed gzip stream.
+
+ .. versionadded:: 0.8.5
+
+ Added support for using bytes instead of str in Python 3
+
+ .. method:: next()
+
+ A TagFile is its own iterator. This method is part of the iterator
+ protocol and returns a :class:`TagSection` object for the next
+ section in the file. If there is no further section, this method
+ raises the :exc:`StopIteration` exception.
+
+ From Python 3 on, this method is not available anymore, and the
+ global function ``next()`` replaces it.
+
+ The second API uses a shared :class:`TagSection` object which is exposed
+ through the :attr:`section` attribute. This object is modified by calls
+ to :meth:`step` and :meth:`jump`. This API provides more control and may
+ use less memory, but is not recommended because it works by modifying
+ one object. It can be used like this::
+
+ with apt_pkg.TagFile('/var/lib/dpkg/status') as tagf:
+ tagf.step()
+ print tagf.section['Package']
+
+ .. method:: step() -> bool
+
+ Step forward to the next section. This simply returns ``True`` if OK,
+ and ``False`` if there is no section.
+
+ .. method:: offset() -> int
+
+ Return the current offset (in bytes) from the beginning of the file.
+
+ .. method:: jump(offset) -> bool
+
+ Jump back/forward to *offset*. Use ``jump(0)`` to jump to the
+ beginning of the file again. Returns ``True`` if a section could
+ be parsed or ``False`` if not.
+
+ .. attribute:: section
+
+ This is the current :class:`TagSection()` instance.
+
+.. class:: TagSection(text)
+
+ Represent a single section of a debian control file.
+
+ .. describe:: section[key]
+
+ Return the value of the field at *key*. If *key* is not available,
+ raise :exc:`KeyError`.
+
+ .. describe:: key in section
+
+ Return ``True`` if *section* has a key *key*, else ``False``.
+
+ .. versionadded:: 0.7.100
+
+ .. method:: bytes() -> int
+
+ The number of bytes in the section.
+
+ .. method:: find(key: str, default: str = '') -> str
+
+ Return the value of the field at the key *key* if available,
+ else return *default*.
+
+ .. method:: find_flag(key: str) -> bool
+
+ Find a yes/no value for the key *key*. An example for such a
+ field is 'Essential'.
+
+ .. method:: find_raw(key: str, default: str = '') -> str
+
+ Similar to :meth:`find`, but instead of returning just the value,
+ it returns the complete field consisting of 'key: value'.
+
+ .. method:: get(key: str, default: str = '')
+
+ Return the value of the field at the key *key* if available, else
+ return *default*.
+
+ .. method:: keys()
+
+ Return a list of keys in the section.
+
+
+ .. automethod:: write
+
+
+A function can be rewritten by using tag classes:
+
+.. autoclass:: Tag
+ :members:
+
+ The following static members can be used to determine the meaning of
+ :attr:`action`:
+
+ .. data:: REWRITE
+
+ Change the field value to the value of :attr:`data`
+
+ .. data:: RENAME
+
+ Rename the tag to a new tag stored in :attr:`data`.
+
+ .. data:: REMOVE
+
+ Remove the tag.
+
+ Apart from this, the class provides access to several attributes.
+
+.. autoclass:: TagRewrite
+
+.. autoclass:: TagRemove
+
+.. autoclass:: TagRename
+
+Pre-defined ordering for tag sections are:
+
+.. data:: REWRITE_PACKAGE_ORDER
+
+ The order in which the information for binary packages should be rewritten,
+ i.e. the order in which the fields should appear.
+
+.. data:: REWRITE_SOURCE_ORDER
+
+ The order in which the information for source packages should be rewritten,
+ i.e. the order in which the fields should appear.
+
+
+Dependencies
+------------
+.. function:: check_dep(pkgver: str, op: str, depver: str) -> bool
+
+ Check that the given requirement is fulfilled; that is, that the version
+ string given by *pkg_ver* matches the version string *dep_ver* under
+ the condition specified by the operator 'dep_op' (<,<=,=,>=,>).
+
+ Return True if *pkg_ver* matches *dep_ver* under the condition 'dep_op';
+ for example::
+
+ >>> apt_pkg.check_dep("1.0", ">=", "1")
+ True
+
+The following two functions provide the ability to parse dependencies. They
+use the same format as :attr:`Version.depends_list_str`.
+
+.. function:: parse_depends(depends, strip_multiarch=True, architecture)
+
+ Parse the string *depends* which contains dependency information as
+ specified in Debian Policy, Section 7.1.
+
+ Returns a list. The members of this list are lists themselves and contain
+ one or more tuples in the format ``(package,version,operation)`` for every
+ 'or'-option given, e.g.::
+
+ >>> apt_pkg.parse_depends("PkgA (>= VerA) | PkgB (>= VerB)")
+ [[('PkgA', 'VerA', '>='), ('PkgB', 'VerB', '>=')]]
+
+ Note that multiarch dependency information is stripped off by default.
+ You can force the full dependency info (including the multiarch info)
+ by passing "False" as a additional parameter to this function.
+
+ You can specify an optional argument *architecture* that treats the given
+ architecture as the native architecture for purposes of parsing the
+ dependency.
+
+ .. note::
+
+ The behavior of this function is different than the behavior of the
+ old function :func:`ParseDepends()`, because the third field
+ ``operation`` uses `>` instead of `>>` and `<` instead of `<<` which
+ is specified in control files.
+
+
+.. function:: parse_src_depends(depends, strip_multiarch=True, architecture)
+
+ Parse the string *depends* which contains dependency information as
+ specified in Debian Policy, Section 7.1.
+
+ Returns a list. The members of this list are lists themselves and contain
+ one or more tuples in the format ``(package,version,operation)`` for every
+ 'or'-option given, e.g.::
+
+ >>> apt_pkg.parse_depends("PkgA (>= VerA) | PkgB (>= VerB)")
+ [[('PkgA', 'VerA', '>='), ('PkgB', 'VerB', '>=')]]
+
+
+ Furthemore, this function also supports to limit the architectures, as
+ used in e.g. Build-Depends::
+
+ >>> apt_pkg.parse_src_depends("a (>= 01) [i386 amd64]")
+ [[('a', '01', '>=')]]
+
+ Note that multiarch dependency information is stripped off by default.
+ You can force the full dependency info (including the multiarch info)
+ by passing "False" as a additional parameter to this function.
+
+ You can specify an optional argument *architecture* that treats the given
+ architecture as the native architecture for purposes of parsing the
+ dependency.
+
+ .. note::
+
+ The behavior of this function is different than the behavior of the
+ old function :func:`ParseDepends()`, because the third field
+ ``operation`` uses `>` instead of `>>` and `<` instead of `<<` which
+ is specified in control files.
+
+
+Configuration and Command-line parsing
+--------------------------------------
+
+.. class:: Configuration()
+
+ Provide access to and manipulation of APT's configuration which is
+ used by many classes and functions in this module to define their
+ behavior. There are options to install recommends, change the root
+ directory and much more. For an (incomplete) list of available options,
+ see the :manpage:`apt.conf(5)` manual page.
+
+ The most important Configuration object is the one available by the
+ module's :attr:`apt_pkg.config` attribute. It stores the global
+ configuration which affects the behavior of most functions and is
+ initialized by a call to the function :func:`init_config`. While
+ possible, it is generally not needed to create other instances of
+ this class.
+
+ For accessing and manipulating the configuration space, objects
+ of this type provide an interface which resembles Python mapping
+ types like :class:`dict`.
+
+ .. describe:: key in conf
+
+ Return ``True`` if *conf* has a key *key*, else ``False``.
+
+ .. describe:: conf[key]
+
+ Return the value of the option given key *key*. If it does not
+ exist, raise :exc:`KeyError`.
+
+ .. describe:: conf[key] = value
+
+ Set the option at *key* to *value*.
+
+ .. describe del conf[key]
+
+ Delete the option with the name *key* in the configuration object
+ *conf*.
+
+ .. method:: get(key[, default='']) -> str
+
+ Find the value for the given key and return it. If the given key does
+ not exist, return *default* instead.
+
+ In addition, they provide methods to resemble the interface provided
+ by the C++ class and some more mapping methods which have been enhanced
+ to support some more advanced configuration features:
+
+ .. method:: clear(key: str)
+
+ Remove the option at *key* and all of its children.
+
+ .. method:: dump() -> str
+
+ Return a string containing the values in the configuration object,
+ in the standard :manpage:`apt.conf(5)` format.
+
+ .. versionadded:: 0.7.100
+
+ .. method:: exists(key)
+
+ Check whether an option named *key* exists in the configuration.
+
+ .. method:: find(key[, default='']) -> str
+
+ Return the value stored at the option named *key*, or the value
+ given by the string *default* if the option in question is not
+ set.
+
+ .. method:: find_b(key[, default=False]) -> bool
+
+ Return the boolean value stored at *key*, or the value given by
+ the :class:`bool` object *default* if the requested option is
+ not set.
+
+ .. method:: find_file(key[, default='']) -> str
+ find_dir(key[, default='/']) -> str
+
+ Locate the given key using :meth:`find` and return the path to the
+ file/directory. This uses a special algorithms which moves upwards
+ in the configuration space and prepends the values of the options
+ to the result. These methods are generally used for the options
+ stored in the 'Dir' section of the configuration.
+
+ As an example of how this works, take a look at the following options
+ and their values:
+
+ .. table::
+
+ ============== ===========================
+ Option Value
+ ============== ===========================
+ Dir /
+ Dir::Etc etc/apt/
+ Dir::Etc::main apt.conf
+ ============== ===========================
+
+ A call to :meth:`find_file` would now return ``/etc/apt/apt.conf``
+ because it prepends the values of "Dir::Etc" and "Dir" to the value
+ of "Dir::Etc::main"::
+
+ >>> apt_pkg.config.find_file("Dir::Etc::main")
+ '/etc/apt/apt.conf'
+
+ If the special configuration variable "RootDir" is set, this value
+ would be prepended to every return value, even if the path is already
+ absolute. If not, the function ends as soon as an absolute path is
+ created (once an option with a value starting with "/" is read).
+
+ The method :meth:`find_dir` does exactly the same thing as
+ :meth:`find_file`, but adds a trailing forward slash before
+ returning the value.
+
+ .. method:: find_i(key[, default=0]) -> int
+
+ Return the integer value stored at *key*, or the value given by
+ the integer *default* if the requested option is not set.
+
+ .. method:: keys([key])
+
+ Return a recursive list of all configuration options or, if *key*
+ is given, a list of all its children. This method is comparable
+ to the **keys** method of a mapping object, but additionally
+ provides the parameter *key*.
+
+ .. method:: list([key])
+
+ Return a non-recursive list of all configuration options. If *key*
+ is not given, this returns a list of options like "Apt", "Dir", and
+ similar. If *key* is given, a list of the names of its child options
+ will be returned instead.
+
+ .. method:: my_tag()
+
+ Return the tag name of the current tree. Normally (for
+ :data:`apt_pkg.config`) this is an empty string, but for
+ sub-trees it is the key of the sub-tree.
+
+ .. method:: set(key: str, value: str)
+
+ Set the option named *key* to the value given by the argument
+ *value*. It is possible to store objects of the types :class:`int`
+ and :class:`bool` by calling :func:`str` on them to convert them
+ to a string object. They can then be retrieved again by using the
+ methods :meth:`find_i` or :meth:`find_b`.
+
+ .. method:: subtree(key)
+
+ Return a new apt_pkg.Configuration object which starts at the
+ given option. Example::
+
+ apttree = config.subtree('APT')
+ apttree['Install-Suggests'] = config['APT::Install-Suggests']
+
+ The configuration space is shared with the main object which means
+ that all modifications in one object appear in the other one as
+ well.
+
+ .. method:: value_list([key])
+
+ This is the opposite of the :meth:`list` method in that it returns the
+ values instead of the option names.
+
+.. data:: config
+
+ This variable contains the global configuration which is used by
+ all classes and functions in this module. After importing the
+ module, this object should be initialized by calling the module's
+ :func:`init_config` function.
+
+.. function:: read_config_file(configuration: Configuration, filename: str)
+
+ Read the configuration file *filename* and set the appropriate
+ options in the configuration object *configuration*.
+
+.. function:: read_config_dir(configuration, dirname)
+
+ Read all configuration files in the dir given by 'dirname' in the
+ correct order.
+
+
+.. function:: read_config_file_isc(configuration, filename)
+
+ Read the configuration file *filename* and set the appropriate
+ options in the configuration object *configuration*. This function
+ requires a slightly different format than APT configuration files,
+ if you are unsure, do not use it.
+
+.. function:: parse_commandline(configuration, options, argv)
+
+ Parse the command line in *argv* into the configuration space. The
+ list *options* contains a list of 3-tuples or 4-tuples in the form::
+
+ (short_option: str, long_option: str, variable: str[, type: str])
+
+ The element *short_option* is one character, the *long_option* element
+ is the name of the long option, the element *variable* the name of the
+ configuration option the result will be stored in and *type* is one of
+ 'HasArg', 'IntLevel', 'Boolean', 'InvBoolean', 'ConfigFile',
+ 'ArbItem'. The default type is 'Boolean'.
+
+ .. table:: Overview of all possible types
+
+ =========== =====================================================
+ Type What happens if the option is given
+ =========== =====================================================
+ HasArg The argument given to the option is stored in
+ the target.
+ IntLevel The integer value in the target is increased by one
+ Boolean The target variable is set to True.
+ InvBoolean The target variable is set to False.
+ ConfigFile The file given as an argument to this option is read
+ in and all configuration options are added to the
+ configuration object (APT's '-c' option).
+ ArbItem The option takes an argument *key*=*value*, and the
+ configuration option at *key* is set to the value
+ *value* (APT's '-o' option).
+ =========== =====================================================
+
+
+Locking
+--------
+When working on the global cache, it is important to lock the cache so other
+programs do not modify it. This module provides two context managers for
+locking the package system or file-based locking.
+
+.. class:: SystemLock
+
+ Context manager for locking the package system. The lock is established
+ as soon as the method __enter__() is called. It is released when
+ __exit__() is called. If the lock can not be acquired or can not be
+ released an exception is raised.
+
+ This should be used via the 'with' statement. For example::
+
+ with apt_pkg.SystemLock():
+ ... # Do your stuff here.
+ ... # Now it's unlocked again
+
+ Once the block is left, the lock is released automatically. The object
+ can be used multiple times::
+
+ lock = apt_pkg.SystemLock()
+ with lock:
+ ...
+ with lock:
+ ...
+
+.. class:: FileLock(filename: str)
+
+ Context manager for locking using a file. The lock is established
+ as soon as the method __enter__() is called. It is released when
+ __exit__() is called. If the lock can not be acquired or can not be
+ released, an exception is raised.
+
+ This should be used via the 'with' statement. For example::
+
+ with apt_pkg.FileLock(filename):
+ ...
+
+ Once the block is left, the lock is released automatically. The object
+ can be used multiple times::
+
+ lock = apt_pkg.FileLock(filename)
+ with lock:
+ ...
+ with lock:
+ ...
+
+For Python versions prior to 2.5, similar functionality is provided by the
+following three functions:
+
+.. function:: get_lock(filename: str, errors=False) -> int
+
+ Create an empty file at the path specified by the parameter *filename* and
+ lock it. If this fails and *errors* is **True**, the function raises an
+ error. If *errors* is **False**, the function returns -1.
+
+ The lock can be acquired multiple times within the same process, and can be
+ released by calling :func:`os.close` on the return value which is the file
+ descriptor of the created file.
+
+.. function:: pkgsystem_lock()
+
+ Lock the global pkgsystem. The lock should be released by calling
+ :func:`pkgsystem_unlock` again. If this function is called n-times, the
+ :func:`pkgsystem_unlock` function must be called n-times as well to release
+ all acquired locks.
+
+.. function:: pkgsystem_unlock()
+
+ Unlock the global pkgsystem. This reverts the effect of
+ :func:`pkgsystem_lock`.
+
+Since version 1.7, APT switches to the frontend locking approach where
+dpkg has two lock files, :file:`lock-frontend` and :file:`lock`, the
+latter being called the inner lock in apt.
+When running dpkg, the inner lock must be released before calling dpkg
+and reacquired afterwards. When not using APT functions to run dpkg,
+the variable `DPKG_FRONTEND_LOCKED` must be set to tell dpkg to not
+acquire the :file:`lock-frontend` lock.
+These functions usually do not need to be used by external code.
+
+.. function:: pkgsystem_unlock_inner()
+
+ Release the :file:`lock` lock file to allow dpkg to be run.
+
+ .. versionadded:: 1.7
+
+.. function:: pkgsystem_lock_inner()
+
+ Release the :file:`lock` lock file after a dpkg run.
+
+ .. versionadded:: 1.7
+
+.. function:: pkgsystem_is_locked()
+
+ Returns true if the global lock is hold. Can be used to check whether
+ :meth:`pkgsystem_unlock_inner` needs to be called.
+
+ .. versionadded:: 1.7
+
+
+
+Other classes
+--------------
+.. class:: Cdrom()
+
+ A Cdrom object identifies Debian installation media and adds them to
+ :file:`/etc/apt/sources.list`. The C++ version of this class is used by
+ the apt-cdrom tool and using this class, you can re-implement apt-cdrom
+ in Python, see :doc:`../tutorials/apt-cdrom`.
+
+ The class :class:`apt.cdrom.Cdrom` is a subclass of this class and
+ provides some additional functionality for higher level use and some
+ shortcuts for setting some related configuration options.
+
+ This class provides two functions which take an instance of
+ :class:`apt.progress.base.CdromProgress` as their argument.
+
+ .. method:: add(progress: apt.progress.base.CdromProgress) -> bool
+
+ Search for a Debian installation media and add it to the list of
+ sources stored in :file:`/etc/apt/sources.list`. On success, the
+ boolean value ``True`` is returned. If the process failed or was
+ canceled by the progress class, :exc:`SystemError` is raised or
+ ``False`` is returned.
+
+ .. method:: ident(progress: apt.progress.base.CdromProgress) -> str
+
+ Identify the installation media and return a string which describes
+ its identity. If no media could be identified, :exc:`SystemError` is
+ raised or ``None`` is returned.
+
+.. class:: SourceList
+
+ Represent the list of sources stored in files such as
+ :file:`/etc/apt/sources.list`.
+
+ .. method:: find_index(pkgfile: PackageFile) -> IndexFile
+
+ Return the :class:`IndexFile` object for the :class:`PackageFile`
+ object given by the argument *pkgfile*. If no index could be found,
+ return ``None``.
+
+ .. method:: get_indexes(acquire: Acquire[, all: bool = False]) -> bool
+
+ Add all indexes to the :class:`Acquire` object given by the argument
+ *acquire*. If *all* is ``True``, all indexes will be added, otherwise
+ only the meta indexes (Release files) will be added and others are
+ fetched as needed.
+
+ .. method:: read_main_list() -> bool
+
+ Read the files configured in Dir::Etc::SourceList and
+ Dir::Etc::sourceparts; that is (on normal system),
+ :file:`/etc/apt/sources.list` and the files in
+ :file:`/etc/apt/sources.list.d`.
+
+ .. attribute:: list
+
+ A list of :class:`MetaIndex` objects.
+
+String functions
+----------------
+.. function:: base64_encode(value: bytes) -> str
+
+ Encode the given bytes string (which may not contain a null byte)
+ using base64, for example, on Python 3 and newer::
+
+ >>> apt_pkg.base64_encode(b"A")
+ 'QQ=='
+
+ on Python versions prior to 3, the 'b' before the string has to be
+ omitted.
+
+.. function:: check_domain_list(host, list)
+
+ See if the host name given by *host* is one of the domains given in the
+ comma-separated list *list* or a subdomain of one of them.
+
+ >>> apt_pkg.check_domain_list("alioth.debian.org","debian.net,debian.org")
+ True
+
+.. function:: dequote_string(string: str)
+
+ Dequote the string specified by the parameter *string*, e.g.::
+
+ >>> apt_pkg.dequote_string("%61%70%74%20is%20cool")
+ 'apt is cool'
+
+.. function:: quote_string(string, repl)
+
+ Escape the string *string*, replacing any character not allowed in a URL
+ or specified by *repl* with its ASCII value preceded by a percent sign
+ (so for example ' ' becomes '%20').
+
+ >>> apt_pkg.quote_string("apt is cool","apt")
+ '%61%70%74%20is%20cool'
+
+.. function:: size_to_str(size: int)
+
+ Return a string describing the size in a human-readable manner using
+ SI prefix and base-10 units, e.g. '1k' for 1000, '1M' for 1000000, etc.
+
+ Example::
+
+ >>> apt_pkg.size_to_str(10000)
+ '10.0k'
+
+.. function:: string_to_bool(input)
+
+ Parse the string *input* and return one of **-1**, **0**, **1**.
+
+ .. table:: Return values
+
+ ===== =============================================
+ Value Meaning
+ ===== =============================================
+ -1 The string *input* is not recognized.
+ 0 The string *input* evaluates to **False**.
+ +1 The string *input* evaluates to **True**.
+ ===== =============================================
+
+ Example::
+
+ >>> apt_pkg.string_to_bool("yes")
+ 1
+ >>> apt_pkg.string_to_bool("no")
+ 0
+ >>> apt_pkg.string_to_bool("not-recognized")
+ -1
+
+
+.. function:: str_to_time(rfc_time)
+
+ Convert the :rfc:`1123` conforming string *rfc_time* to the unix time, and
+ return the integer. This is the opposite of :func:`TimeRFC1123`.
+
+ Example::
+
+ >> apt_pkg.str_to_time('Thu, 01 Jan 1970 00:00:00 GMT')
+ 0
+
+.. function:: time_rfc1123(seconds: int) -> str
+
+ Format the unix time specified by the integer *seconds*, according to the
+ requirements of :rfc:`1123`.
+
+ Example::
+
+ >>> apt_pkg.time_rfc1123(0)
+ 'Thu, 01 Jan 1970 00:00:00 GMT'
+
+
+.. function:: time_to_str(seconds: int) -> str
+
+ Format a given duration in a human-readable manner. The parameter *seconds*
+ refers to a number of seconds, given as an integer. The return value is a
+ string with a unit like 's' for seconds.
+
+ Example::
+
+ >>> apt_pkg.time_to_str(3601)
+ '1h0min1s'
+
+.. function:: upstream_version(version: str) -> str
+
+ Return the upstream version for the Debian package version given by
+ *version*.
+
+.. function:: uri_to_filename(uri: str) -> str
+
+ Take a string *uri* as parameter and return a filename which can be used to
+ store the file, based on the URI.
+
+ Example::
+
+ >>> apt_pkg.uri_to_filename('http://debian.org/index.html')
+ 'debian.org_index.html'
+
+
+.. function:: version_compare(a: str, b: str) -> int
+
+ Compare two versions, *a* and *b*, and return an integer value which has
+ the same meaning as the built-in :func:`cmp` function's return value has,
+ see the following table for details.
+
+ .. table:: Return values
+
+ ===== =============================================
+ Value Meaning
+ ===== =============================================
+ > 0 The version *a* is greater than version *b*.
+ = 0 Both versions are equal.
+ < 0 The version *a* is less than version *b*.
+ ===== =============================================
+
+
+Module Constants
+----------------
+.. _CurStates:
+
+Package States
+^^^^^^^^^^^^^^^
+.. data:: CURSTATE_CONFIG_FILES
+
+ Only the configuration files of the package exist on the system.
+
+.. data:: CURSTATE_HALF_CONFIGURED
+
+ The package is unpacked and configuration has been started, but not
+ yet completed.
+
+.. data:: CURSTATE_HALF_INSTALLED
+
+ The installation of the package has been started, but not completed.
+
+.. data:: CURSTATE_INSTALLED
+
+ The package is unpacked, configured and OK.
+
+.. data:: CURSTATE_NOT_INSTALLED
+
+ The package is not installed.
+
+.. data:: CURSTATE_UNPACKED
+
+ The package is unpacked, but not configured.
+
+.. _InstStates:
+
+Installed states
+^^^^^^^^^^^^^^^^
+.. data:: INSTSTATE_HOLD
+
+ The package is put on hold.
+
+.. data:: INSTSTATE_HOLD_REINSTREQ
+
+ The package is put on hold, but broken and has to be reinstalled.
+
+.. data:: INSTSTATE_OK
+
+ The package is OK.
+
+.. data:: INSTSTATE_REINSTREQ
+
+ The package is broken and has to be reinstalled.
+
+.. _Priorities:
+
+Priorities
+^^^^^^^^^^^
+.. data:: PRI_EXTRA
+
+ The integer representation of the priority 'extra'.
+
+.. data:: PRI_IMPORTANT
+
+ The integer representation of the priority 'important'.
+
+.. data:: PRI_OPTIONAL
+
+ The integer representation of the priority 'optional'.
+
+.. data:: PRI_REQUIRED
+
+ The integer representation of the priority 'required'.
+
+.. data:: PRI_STANDARD
+
+ The integer representation of the priority 'standard'.
+
+
+.. _SelStates:
+
+Package selection states
+^^^^^^^^^^^^^^^^^^^^^^^^
+.. data:: SELSTATE_DEINSTALL
+
+ The package is selected for deinstallation.
+
+.. data:: SELSTATE_HOLD
+
+ The package is marked to be on hold and will not be modified.
+
+.. data:: SELSTATE_INSTALL
+
+ The package is selected for installation.
+
+.. data:: SELSTATE_PURGE
+
+ The package is selected to be purged.
+
+.. data:: SELSTATE_UNKNOWN
+
+ The package is in an unknown state.
+
+
+Build information
+^^^^^^^^^^^^^^^^^
+.. data:: DATE
+
+ The date on which this extension has been compiled.
+
+.. data:: LIB_VERSION
+
+ The version of the apt_pkg library. This is **not** the version of apt,
+ nor the version of python-apt.
+
+.. data:: TIME
+
+ The time this extension has been built.
+
+.. data:: VERSION
+
+ The version of apt (not of python-apt).
diff --git a/doc/source/library/aptsources.distinfo.rst b/doc/source/library/aptsources.distinfo.rst
new file mode 100644
index 0000000..033ef48
--- /dev/null
+++ b/doc/source/library/aptsources.distinfo.rst
@@ -0,0 +1,11 @@
+:mod:`aptsources.distinfo` --- provide meta information for distro repositories
+===============================================================================
+.. note::
+
+ This part of the documentation is created automatically.
+
+
+.. automodule:: aptsources.distinfo
+ :members:
+ :undoc-members:
+
diff --git a/doc/source/library/aptsources.distro.rst b/doc/source/library/aptsources.distro.rst
new file mode 100644
index 0000000..6ebe438
--- /dev/null
+++ b/doc/source/library/aptsources.distro.rst
@@ -0,0 +1,11 @@
+:mod:`aptsources.distro` --- Distribution abstraction of the sources.list
+===============================================================================
+.. note::
+
+ This part of the documentation is created automatically.
+
+
+.. automodule:: aptsources.distro
+ :members:
+ :undoc-members:
+
diff --git a/doc/source/library/aptsources.sourceslist.rst b/doc/source/library/aptsources.sourceslist.rst
new file mode 100644
index 0000000..79b8dd0
--- /dev/null
+++ b/doc/source/library/aptsources.sourceslist.rst
@@ -0,0 +1,11 @@
+:mod:`aptsources.sourceslist` --- Provide an abstraction of the sources.list
+============================================================================
+.. note::
+
+ This part of the documentation is created automatically.
+
+
+.. automodule:: aptsources.sourceslist
+ :members:
+ :undoc-members:
+
diff --git a/doc/source/library/index.rst b/doc/source/library/index.rst
new file mode 100644
index 0000000..0b048c8
--- /dev/null
+++ b/doc/source/library/index.rst
@@ -0,0 +1,35 @@
+Python APT Library
+==================
+Python APT's library provides access to almost every functionality supported
+by the underlying apt-pkg and apt-inst libraries. This means that it is
+possible to rewrite frontend programs like apt-cdrom in Python, and this is
+relatively easy, as can be seen in e.g. :doc:`../tutorials/apt-cdrom`.
+
+When going through the library, the first two modules are :mod:`apt_pkg` and
+:mod:`apt_inst`. These modules are more or less straight bindings to the
+apt-pkg and apt-inst libraries and the base for the rest of python-apt.
+
+Going forward, the :mod:`apt` package appears. This package is using
+:mod:`apt_pkg` and :mod:`apt_inst` to provide easy to use ways to manipulate
+the cache, fetch packages, or install new packages. It also provides useful
+progress classes, currently only for text interfaces. The last package is
+:mod:`aptsources`. The aptsources package provides classes and functions to
+read files like :file:`/etc/apt/sources.list` and to modify them.
+
+.. toctree::
+ :maxdepth: 1
+
+ apt_pkg
+ apt_inst
+
+ apt.cache
+ apt.cdrom
+ apt.debfile
+ apt.package
+ apt.progress.base
+ apt.progress.text
+
+ aptsources.distinfo
+ aptsources.distro
+ aptsources.sourceslist
+