X-Git-Url: https://git.saurik.com/apt.git/blobdiff_plain/3e2d7cce4febc923d4b9bcb363717dd161cbb856..4011e1137955decbb988e0098ba9f4fdbe6f2e4d:/doc/apt.conf.5.xml
diff --git a/doc/apt.conf.5.xml b/doc/apt.conf.5.xml
index 2b2430c83..0cd63b31c 100644
--- a/doc/apt.conf.5.xml
+++ b/doc/apt.conf.5.xml
@@ -21,12 +21,13 @@
&apt-email;
&apt-product;
- 10 December 2008
+ 18 September 2009
apt.conf
5
+ APT
@@ -58,8 +59,12 @@
between /* and */, just like C/C++ comments.
Each line is of the form
APT::Get::Assume-Yes "true"; The trailing
- semicolon is required and the quotes are optional. A new scope can be
- opened with curly braces, like:
+ semicolon and the quotes are required. The value must be on one line, and
+ there is no kind of string concatenation. It must not include inside quotes.
+ The behavior of the backslash "\" and escaped characters inside a value is
+ undefined and it should not be used. An option name may include
+ alphanumerical characters and the "/-:._+" characters. A new scope can
+ be opened with curly braces, like:
APT {
@@ -85,17 +90,41 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
The names of the configuration items are not case-sensitive. So in the previous example
you could use dpkg::pre-install-pkgs.
- Two specials are allowed, #include and #clear
+ Names for the configuration items are optional if a list is defined as it can be see in
+ the DPkg::Pre-Install-Pkgs 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.
+
+ Two specials are allowed, #include (which is deprecated
+ and not supported by alternative implementations) and #clear:
#include will include the given file, unless the filename
ends in a slash, then the whole directory is included.
#clear is used to erase a part of the configuration tree. The
- specified element and all its descendents are erased.
+ specified element and all its descendants are erased.
+ (Note that these lines also need to end with a semicolon.)
+
+ The #clear command is the only way to delete a list or a complete scope.
+ Reopening a scope or the ::-style described below will not
+ 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.
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 (APT::Get::Assume-Yes 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.
+ a trailing :: to the list name. (As you might suspect: The scope syntax can't be used
+ on the command line.)
+
+ 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 "::"
+ which acts like every other option with a name. These introduces many problems
+ including that a user who writes multiple lines in this wrong syntax in
+ the hope to append to a list will gain the opposite as only the last assignment for this option
+ "::" 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.
The APT Group
@@ -127,11 +156,22 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
Immediate-Configure
- Disable Immediate Configuration; This dangerous option disables some
- of APT's ordering code to cause it to make fewer dpkg calls. Doing
- so may be necessary on some extremely slow single user systems but
- is very dangerous and may cause package install scripts to fail or worse.
- Use at your own risk.
+ Defaults to on which will cause APT to install essential and important packages
+ as fast as possible in the install/upgrade operation. This is done to limit the effect of a failing
+ &dpkg; call: If this option is disabled APT doesn't treat an important package in the same way as
+ an extra package: Between the unpacking of the important package A and his configuration can then
+ be many other unpack or configuration calls, e.g. for package B which has no relation to A, but
+ causes the dpkg call to fail (e.g. because maintainer script of package B generates an error) which results
+ in a system state in which package A is unpacked but unconfigured - each package depending on A is now no
+ longer guaranteed to work as their dependency on A is not longer satisfied. The immediate configuration marker
+ is also applied to all dependencies which can generate a problem if the dependencies e.g. form a circle
+ as a dependency with the immediate flag is comparable with a Pre-Dependency. So in theory it is possible
+ that APT encounters a situation in which it is unable to perform immediate configuration, error out and
+ refers to this option so the user can deactivate the immediate configuration temporary to be able to perform
+ an install/upgrade again. Note the use of the word "theory" here as this problem was only encountered by now
+ in real world a few times in non-stable distribution versions and caused by wrong dependencies of the package
+ in question, so you should not blindly disable this option as the mentioned scenario above is not the only
+ problem immediate configuration can help to prevent in the first place.
Force-LoopBreak
@@ -203,8 +243,9 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
standard form of http://[[user][:pass]@]host[:port]/. Per
host proxies can also be specified by using the form
http::Proxy::<host> with the special keyword DIRECT
- meaning to use no proxies. The http_proxy environment variable
- will override all settings.
+ meaning to use no proxies. If no one of the above settings is specified,
+ http_proxy environment variable
+ will be used.
Three settings are provided for cache control with HTTP/1.1 compliant
proxy caches. No-Cache tells the proxy to not use its cached
@@ -225,7 +266,12 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
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.
+ require this are in violation of RFC 2068.
+
+ The used bandwidth can be limited with Acquire::http::Dl-Limit
+ 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.)
https
@@ -252,9 +298,13 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
ftp
- FTP URIs; ftp::Proxy is the default proxy server to use. It is in the
- standard form of ftp://[[user][:pass]@]host[:port]/ and is
- overridden by the ftp_proxy environment variable. To use a ftp
+ FTP URIs; ftp::Proxy is the default ftp proxy to use. It is in the
+ standard form of ftp://[[user][:pass]@]host[:port]/. Per
+ host proxies can also be specified by using the form
+ ftp::Proxy::<host> with the special keyword DIRECT
+ meaning to use no proxies. If no one of the above settings is specified,
+ ftp_proxy environment variable
+ will be used. To use a ftp
proxy you will have to set the ftp::ProxyLogin script in the
configuration file. This entry specifies the commands to send to tell
the proxy server what to connect to. Please see
@@ -292,7 +342,7 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
as specified in /etc/fstab. It is possible to provide
alternate mount and unmount commands if your mount point cannot be listed
in the fstab (such as an SMB mount and old mount packages). The syntax
- is to put "/cdrom/"::Mount "foo"; within
+ is to put /cdrom/::Mount "foo"; within
the cdrom block. It is important to have the trailing slash. Unmount
commands can be specified using UMount.
@@ -303,6 +353,34 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
+ CompressionTypes
+ List of compression types which are understood by the acquire methods.
+ Files like Packages can be available in various compression formats.
+ Per default the acquire methods can decompress bzip2, lzma
+ and gzip compressed files, with this setting more formats can be added
+ on the fly or the used method can be changed. The syntax for this is:
+ Acquire::CompressionTypes::FileExtension "Methodname";
+ Also the Order subgroup can be used to define in which order
+ the acquire system will try to download the compressed files. The acquire system will try the first
+ and proceed with the next compression type in this list on error, so to prefer one over the other type
+ simple add the preferred type at first - not already added default types will be added at run time
+ to the end of the list, so e.g. Acquire::CompressionTypes::Order:: "gz"; can
+ be used to prefer gzip compressed files over bzip2 and lzma.
+ If lzma should be preferred over gzip and bzip2 the
+ configure setting should look like this Acquire::CompressionTypes::Order { "lzma"; "gz"; };
+ It is not needed to add bz2 explicit to the list as it will be added automatic.
+ Note that at run time the Dir::Bin::Methodname 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 Dir::Bin::bzip2 "/bin/bzip2";
+ 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.
+ While it is possible to add an empty compression type to the order list, but APT in its current
+ version doesn't understand it correctly and will display many warnings about not downloaded files -
+ these warnings are most of the time false negatives. Future versions will maybe include a way to
+ really prefer uncompressed files to support the usage of local mirrors.
+
@@ -337,6 +415,7 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
Binary programs are pointed to by Dir::Bin. Dir::Bin::Methods
specifies the location of the method handlers and gzip,
+ bzip2, lzma,
dpkg, apt-get dpkg-source
dpkg-buildpackage and apt-cache specify the location
of the respective programs.
@@ -429,6 +508,87 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
the default is to disable signing and produce all binaries.
+
+ dpkg trigger usage (and related options)
+ 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.
+ These options are therefore currently experimental and should not be used in
+ productive environments. 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.
+ 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. dpkg --audit. A defensive option combination would be
+DPkg::NoTriggers "true";
+PackageManager::Configure "smart";
+DPkg::ConfigurePending "true";
+DPkg::TriggersPending "true";
+
+
+ DPkg::NoTriggers
+ 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.
+
+ PackageManager::Configure
+ Valid values are "all", "smart" and "no".
+ "all" is the default value and causes APT to configure all packages explicit.
+ The "smart" 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. "no" 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!
+
+
+ DPkg::ConfigurePending
+ If this option is set apt will call dpkg --configure --pending
+ to let dpkg handle all required configurations and triggers. This option is activated automatic
+ per default if the previous option is not set to all, 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.
+
+ DPkg::TriggersPending
+ Useful for smart configuration as a package which has pending
+ triggers is not considered as installed and dpkg treats them as unpacked
+ 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.
+
+ PackageManager::UnpackAll
+ 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 OrderCritical method was unused, so
+ this method is very experimental and needs further improvements before becoming really useful.
+
+
+ OrderList::Score::Immediate
+ 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 DPkg::TriggersPending 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.
+ OrderList::Score {
+ Delete 500;
+ Essential 200;
+ Immediate 10;
+ PreDepends 50;
+};
+
+
+
+
@@ -822,7 +982,9 @@ is commented.
Files
- /etc/apt/apt.conf
+
+ &file-aptconf;
+
See Also