&apt-email;
&apt-product;
<!-- The last update date -->
- <date>10 December 2008</date>
+ <date>18 September 2009</date>
</refentryinfo>
<refmeta>
<para>The names of the configuration items are not case-sensitive. So in the previous example
you could use <literal>dpkg::pre-install-pkgs</literal>.</para>
- <para>Two specials are allowed, <literal>#include</literal> and <literal>#clear</literal>
+ <para>Names for the configuration items are optional if a list is defined as it can be see in
+ the <literal>DPkg::Pre-Install-Pkgs</literal> example above. If you don't specify a name a
+ new entry will simply add a new option to the list. If you specify a name you can override
+ the option as every other option by reassigning a new value to the option.</para>
+
+ <para>Two specials are allowed, <literal>#include</literal> and <literal>#clear</literal>:
<literal>#include</literal> will include the given file, unless the filename
ends in a slash, then the whole directory is included.
<literal>#clear</literal> is used to erase a part of the configuration tree. The
- specified element and all its descendants are erased.</para>
+ specified element and all its descendants are erased.
+ (Note that these lines also need to end with a semicolon.)</para>
+
+ <para>The #clear command is the only way to delete a list or a complete scope.
+ Reopening a scope or the ::-style described below will <emphasis>not</emphasis>
+ override previously written entries. Only options can be overridden by addressing a new
+ value to it - lists and scopes can't be overridden, only cleared.</para>
<para>All of the APT tools take a -o option which allows an arbitrary configuration
directive to be specified on the command line. The syntax is a full option
name (<literal>APT::Get::Assume-Yes</literal> for instance) followed by an equals
sign then the new value of the option. Lists can be appended too by adding
- a trailing :: to the list name.</para>
+ a trailing :: to the list name. (As you might suspect: The scope syntax can't be used
+ on the command line.)</para>
+
+ <para>Note that you can use :: only for appending one item per line to a list and
+ that you should not use it in combination with the scope syntax.
+ (The scope syntax implicit insert ::) Using both syntaxes together will trigger a bug
+ which some users unfortunately relay on: An option with the unusual name "<literal>::</literal>"
+ which acts like every other option with a name. These introduces many problems
+ including that a user who writes multiple lines in this <emphasis>wrong</emphasis> syntax in
+ the hope to append to a list will gain the opposite as only the last assignment for this option
+ "<literal>::</literal>" will be used. Upcoming APT versions will raise errors and
+ will stop working if they encounter this misuse, so please correct such statements now
+ as long as APT doesn't complain explicit about them.</para>
</refsect1>
<refsect1><title>The APT Group</title>
indicating how many outstanding requests APT should send. A value of
zero MUST be specified if the remote host does not properly linger
on TCP connections - otherwise data corruption will occur. Hosts which
- require this are in violation of RFC 2068.</para></listitem>
+ require this are in violation of RFC 2068.</para>
+
+ <para>The used bandwidth can be limited with <literal>Acquire::http::Dl-Limit</literal>
+ which accepts integer values in kilobyte. The default value is 0 which deactivates
+ the limit and tries uses as much as possible of the bandwidth (Note that this option implicit
+ deactivates the download from multiple servers at the same time.)</para></listitem>
</varlistentry>
<varlistentry><term>https</term>
<para>Note that at run time the <literal>Dir::Bin::<replaceable>Methodname</replaceable></literal> will
be checked: If this setting exists the method will only be used if this file exists, e.g. for
the bzip2 method (the inbuilt) setting is <literallayout>Dir::Bin::bzip2 "/bin/bzip2";</literallayout>
- Note also that list entries specified on the commandline will be added at the end of the list
+ Note also that list entries specified on the command line will be added at the end of the list
specified in the configuration files, but before the default entries. To prefer a type in this case
over the ones specified in in the configuration files you can set the option direct - not in list style.
This will not override the defined list, it will only prefix the list with this type.</para>
the default is to disable signing and produce all binaries.</para></listitem>
</varlistentry>
</variablelist>
+
+ <refsect2><title>dpkg trigger usage (and related options)</title>
+ <para>APT can call dpkg in a way so it can make aggressive use of triggers over
+ multiply calls of dpkg. Without further options dpkg will use triggers only in between his
+ own run. Activating these options can therefore decrease the time needed to perform the
+ install / upgrade. Note that it is intended to activate these options per default in the
+ future, but as it changes the way APT calling dpkg drastically it needs a lot more testing.
+ <emphasis>These options are therefore currently experimental and should not be used in
+ productive environments.</emphasis> Also it breaks the progress reporting so all frontends will
+ currently stay around half (or more) of the time in the 100% state while it actually configures
+ all packages.</para>
+ <para>Note that it is not guaranteed that APT will support these options or that these options will
+ not cause (big) trouble in the future. If you have understand the current risks and problems with
+ these options, but are brave enough to help testing them create a new configuration file and test a
+ combination of options. Please report any bugs, problems and improvements you encounter and make sure
+ to note which options you have used in your reports. Asking dpkg for help could also be useful for
+ debugging proposes, see e.g. <command>dpkg --audit</command>. A defensive option combination would be
+<literallayout>DPkg::NoTriggers "true";
+PackageManager::Configure "smart";
+DPkg::ConfigurePending "true";
+DPkg::TriggersPending "true";</literallayout></para>
+
+ <variablelist>
+ <varlistentry><term>DPkg::NoTriggers</term>
+ <listitem><para>Add the no triggers flag to all dpkg calls (expect the ConfigurePending call).
+ See &dpkg; if you are interested in what this actually means. In short: dpkg will not run the
+ triggers then this flag is present unless it is explicit called to do so in an extra call.
+ Note that this option exists (undocumented) also in older apt versions with a slightly different
+ meaning: Previously these option only append --no-triggers to the configure calls to dpkg -
+ now apt will add these flag also to the unpack and remove calls.</para></listitem>
+ </varlistentry>
+ <varlistentry><term>PackageManager::Configure</term>
+ <listitem><para>Valid values are "<literal>all</literal>", "<literal>smart</literal>" and "<literal>no</literal>".
+ "<literal>all</literal>" is the default value and causes APT to configure all packages explicit.
+ The "<literal>smart</literal>" way is it to configure only packages which need to be configured before
+ another package can be unpacked (Pre-Depends) and let the rest configure by dpkg with a call generated
+ by the next option. "<literal>no</literal>" on the other hand will not configure anything and totally
+ relay on dpkg for configuration (which will at the moment fail if a Pre-Depends is encountered).
+ Setting this option to another than the all value will implicit activate also the next option per
+ default as otherwise the system could end in an unconfigured status which could be unbootable!
+ </para></listitem>
+ </varlistentry>
+ <varlistentry><term>DPkg::ConfigurePending</term>
+ <listitem><para>If this option is set apt will call <command>dpkg --configure --pending</command>
+ to let dpkg handle all required configurations and triggers. This option is activated automatic
+ per default if the previous option is not set to <literal>all</literal>, but deactivating could be useful
+ if you want to run APT multiple times in a row - e.g. in an installer. In this sceneries you could
+ deactivate this option in all but the last run.</para></listitem>
+ </varlistentry>
+ <varlistentry><term>DPkg::TriggersPending</term>
+ <listitem><para>Useful for <literal>smart</literal> configuration as a package which has pending
+ triggers is not considered as <literal>installed</literal> and dpkg treats them as <literal>unpacked</literal>
+ currently which is a dealbreaker for Pre-Dependencies (see debbugs #526774). Note that this will
+ process all triggers, not only the triggers needed to configure this package.</para></listitem>
+ </varlistentry>
+ <varlistentry><term>PackageManager::UnpackAll</term>
+ <listitem><para>As the configuration can be deferred to be done at the end by dpkg it can be
+ tried to order the unpack series only by critical needs, e.g. by Pre-Depends. Default is true
+ and therefore the "old" method of ordering in various steps by everything. While both method
+ were present in earlier APT versions the <literal>OrderCritical</literal> method was unused, so
+ this method is very experimental and needs further improvements before becoming really useful.
+ </para></listitem>
+ </varlistentry>
+ <varlistentry><term>OrderList::Score::Immediate</term>
+ <listitem><para>Essential packages (and there dependencies) should be configured immediately
+ after unpacking. It will be a good idea to do this quite early in the upgrade process as these
+ these configure calls require currently also <literal>DPkg::TriggersPending</literal> which
+ will run quite a few triggers (which maybe not needed). Essentials get per default a high score
+ but the immediate flag is relatively low (a package which has a Pre-Depends is higher rated).
+ These option and the others in the same group can be used to change the scoring. The following
+ example shows the settings with there default values.
+ <literallayout>OrderList::Score {
+ Delete 500;
+ Essential 200;
+ Immediate 10;
+ PreDepends 50;
+};</literallayout>
+ </para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect2>
</refsect1>
<refsect1>
projects / apt.git / blobdiff