AptPkg::Cache(3pm)

NAME

AptPkg::Cache - APT package cache interface

SYNOPSIS

use AptPkg::Cache;

DESCRIPTION

The AptPkg::Cache module provides an interface to APT's package cache.

AptPkg::Cache

The AptPkg::Cache package implements the APT pkgCacheFile class as a hash reference (inherits from AptPkg::hash). The hash keys are the
names of packages in the cache, and the values are
AptPkg::Cache::Package objects (which in turn appear as hash
references, see below).

Constructor

new([LOCK])

Instantiation of the object uses configuration from the
$AptPkg::Config::_config and $AptPkg::System::_system objects
(automatically initialised if not done explicitly).

The cache initialisation can be quite verbose--controlled by the
value of $_config->{quiet}, which is set to "2" (quiet) if the
$_config object is auto-initialised.

The cache directory is locked if LOCK is true.

It is important to note that the structure of the returned object
contains self-referential elements, so some care must be taken if
attempting to traverse it recursively.

Methods

files

Return a list of AptPkg::Cache::PkgFile objects describing the
package files.

packages

Return an AptPkg::PkgRecords object which may be used to retrieve
additional infomation about packages.

get, exists, keys

These methods are used to implement the hashref abstraction:
$obj->get($pack) and $obj->{$pack} are equivalent.

AptPkg::Cache::Package

Implements the APT pkgCache::PkgIterator class as a hash reference.

Keys

Name
Section

Package name and section.

SelectedState
InstState
CurrentState

Package state from the status file.

SelectedState may be "Unknown", "Install", "Hold", "DeInstall" or
"Purge".

InstState may be "Ok", "ReInstReq", "HoldInst" or "HoldReInstReq".

CurrentState may be "NotInstalled", "UnPacked", "HalfConfigured",
"HalfInstalled", "ConfigFiles" or "Installed".

In a numeric context, SelectedState, InstState and CurrentState
evaluate to an AptPkg::State:: constant.

VersionList

A reference to an array of AptPkg::Cache::Version objects
describing available versions of the package.

CurrentVer

An AptPkg::Cache::Version object describing the currently installed version (if any) of the package.

RevDependsList

A reference to an array of AptPkg::Cache::Depends objects
describing packages which depend upon the current package.

ProvidesList

For virtual packages, this is a reference to an array of
AptPkg::Cache::Provides objects describing packages which provide
the current package.

Flags

A comma seperated list if flags: "Auto", "Essential" or
"Important".

In a numeric context, evaluates to a combination of AptPkg::Flag:: constants.

[Note: the only one of these you need worry about is "Essential", which is set based on the package's header of the same name.
"Auto" seems to be used internally by APT, and "Important" seems to only be set on the apt package.]

Index

Internal APT unique reference for the package record.

AptPkg::Cache::Version

Implements the APT pkgCache::VerIterator class as a hash reference.

Keys

VerStr
Section
Arch

The package version, section and architecture.

ParentPkg

An AptPkg::Cache::Package objct describing the package providing
this version.

DependsList

A reference to an array of AptPkg::Cache::Depends objects
describing packages which the current package depends upon.

ProvidesList

A reference to an array of AptPkg::Cache::Provides objects
describing virtual packages provided by this version.

FileList

A reference to an array of AptPkg::Cache::VerFile objects
describing the packages files which include the current version.

Size

The .deb file size, in bytes.

InstalledSize

The disk space used when installed, in bytes.

Index

Internal APT unique reference for the version record.

Priority

Package priority: "important", "required", "standard", "optional" or "extra".

In a numeric context, evaluates to an AptPkg::VerPriority::
constant.

AptPkg::Cache::Depends

Implements the APT pkgCache::DepIterator class as a hash reference.

Keys

DepType

Type of dependency: "Depends", "PreDepends", "Suggests",
"Recommends", "Conflicts", "Replaces" or "Obsoletes".

In a numeric context, evaluates to an AptPkg::Dep:: constant.

ParentPkg
ParentVer

AptPkg::Cache::Package and AptPkg::Cache::Version objects
describing the package declaring the dependency.

TargetPkg

AptPkg::Cache::Package object describing the depended package.

TargetVer

For versioned dependencies, TargetVer is a string giving the
version of the target package required.

CompType
CompTypeDeb

CompType gives a normalised comparison operator (>, >=, etc)
describing the relationship to TargetVer ("" if none).

CompTypeDeb returns Debian-style operators (>> rather than >).

In a numeric context, both CompType and CompTypeDeb evaluate to an AptPkg::Dep:: constant.

Alternative dependencies (Depends: a | b) are identified by all but the last having the AptPkg::Dep::Or bit set in the numeric
representation of CompType (and CompTypeDeb).

Index

Internal APT unique reference for the dependency record.

AptPkg::Cache::Provides

Implements the APT pkgCache::PrvIterator class as a hash reference.

Keys

Name

Name of virtual package.

OwnerPkg
OwnerVer

AptPkg::Cache::Package and AptPkg::Cache::Version objects
describing the providing package.

ProvideVersion

Version of the virtual package. [Not currently supported by dpkg]

Index

Internal APT unique reference for the provides record.

AptPkg::Cache::VerFile

Implements the APT pkgCache::VerFileIterator class as a hash reference.

Keys

File

An AptPkg::Cache::PkgFile object describing the packages file.

Offset
Size

The byte offset and length of the entry in the file.

Index

Internal APT unique reference for the version file record.

AptPkg::Cache::PkgFile

Implements the APT pkgCache::PkgFileIterator class as a hash reference.

Keys

FileName

Packages file path.

IndexType

File type: "Debian Package Index", "Debian dpkg status file".

Architecture

Architecture.

Archive
Component
Version
Origin
Label
Site

Fields from the Release file.

IsOk

True if the cache is in sync with this file.

Index

Internal APT unique reference for the package file record.

SEE ALSO

AptPkg::Config(3pm), AptPkg::System(3pm), AptPkg(3pm), AptPkg::hash(3pm), AptPkg::PkgRecords(3pm), AptPkg::Policy(3pm).

AUTHOR

Brendan O'Dea <bod@debian.org>

perl v5.10.1 2009-04-16 AptPkg::Cache(3pm)