From 5723791e130a7d28698ae1def407fe15d8de0c32 Mon Sep 17 00:00:00 2001 From: Justin B Rye Date: Sat, 9 Jun 2012 19:14:57 +0200 Subject: * doc/apt.conf.5.xml: - review and fix typo, grammar and style issues - rephrase APT::Immediate-Configuration and many others --- doc/apt.conf.5.xml | 578 ++++++++++++++++++++++++++++------------------------- 1 file changed, 308 insertions(+), 270 deletions(-) (limited to 'doc/apt.conf.5.xml') diff --git a/doc/apt.conf.5.xml b/doc/apt.conf.5.xml index d2784501e..3e304a89d 100644 --- a/doc/apt.conf.5.xml +++ b/doc/apt.conf.5.xml @@ -37,12 +37,13 @@ apt.conf Configuration file for APT - + Description - apt.conf is the main configuration file for - the APT suite of tools, but by far not the only place changes to options - can be made. All tools therefore share the configuration files and also - use a common command line parser to provide a uniform environment. + /etc/apt/apt.conf is the main configuration + file shared by all the tools in the APT suite of tools, though it is by + no means the only place options can be set. The suite also shares a common + command line parser to provide a uniform environment. + When an APT tool starts up it will read the configuration files in the following order: @@ -54,7 +55,7 @@ hyphen (-), underscore (_) and period (.) characters. Otherwise APT will print a notice that it has ignored a file, unless that file matches a pattern in the Dir::Ignore-Files-Silently - configuration list - in this case it will be silently ignored. + configuration list - in which case it will be silently ignored. the main configuration file specified by Dir::Etc::main the command line options are applied to override the @@ -64,7 +65,7 @@ Syntax The configuration file is organized in a tree with options organized into functional groups. Option specification is given with a double colon - notation, for instance APT::Get::Assume-Yes is an option within + notation; for instance APT::Get::Assume-Yes is an option within the APT tool group, for the Get tool. Options do not inherit from their parent groups. @@ -73,13 +74,12 @@ // are treated as comments (ignored), as well as all text between /* and */, just like C/C++ comments. Each line is of the form - APT::Get::Assume-Yes "true";. The trailing - 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::Get::Assume-Yes "true";. + The quotation marks and trailing semicolon are required. + The value must be on one line, and there is no kind of string concatenation. + Values must not include backslashes or extra quotation marks. + Option names are made up of alphanumeric characters and the characters "/-:._+". + A new scope can be opened with curly braces, like this: APT { @@ -92,7 +92,7 @@ APT { with newlines placed to make it more readable. Lists can be created by opening a scope and including a single string enclosed in quotes followed by a - semicolon. Multiple entries can be included, each separated by a semicolon. + semicolon. Multiple entries can be included, separated by a semicolon. DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; @@ -102,44 +102,53 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; &docdir;examples/apt.conf &configureindex; is a good guide for how it should look. - The names of the configuration items are not case-sensitive. So in the previous example - you could use dpkg::pre-install-pkgs. + Case is not significant in names of configuration items, so in the + previous example you could use dpkg::pre-install-pkgs. - Names for the configuration items are optional if a list is defined as it can be see in + Names for the configuration items are optional if a list is defined as can be seen 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. + the option in the same way as any 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. + Two special commands are defined: #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, in which case the whole + directory is included. #clear is used to erase a part of the configuration tree. The 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. + + The #clear command is the only way to delete a list or + a complete scope. Reopening a scope (or using the syntax described below + with an appended ::) will not + override previously written entries. Options can only be overridden by + addressing a new value to them - lists and scopes can't be overridden, + only cleared. + - All of the APT tools take a -o option which allows an arbitrary configuration + All of the APT tools take an -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. To append a new element to a list, add a - trailing :: to the name of the list. (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 depend 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. + trailing :: to the name of the list. + (As you might suspect, the scope syntax can't be used on the command line.) + + + Note that appending items to a list using :: only works + for one item per line, and that you should not use it in combination with + the scope syntax (which adds :: implicitly). Using both + syntaxes together will trigger a bug which some users unfortunately depend + on: an option with the unusual name "::" which acts + like every other option with a name. This introduces many problems; for + one thing, users who write multiple lines in this + wrong syntax in the hope of appending to a list will + achieve the opposite, as only the last assignment for this option + "::" will be used. Future versions of APT will raise + errors and stop working if they encounter this misuse, so please correct + such statements now while APT doesn't explicitly complain about them. + The APT Group @@ -154,23 +163,27 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; - All Architectures the system supports. Processors implementing the - amd64 (also called x86-64) instruction set are - e.g. also able to execute binaries compiled for the i386 - (x86) instruction set; This list is use when fetching files and - parsing package lists. The internal default is always the native architecture (APT::Architecture) - and all foreign architectures it can retrieve by calling dpkg --print-foreign-architectures. + + All Architectures the system supports. For instance, CPUs implementing + the amd64 (also called x86-64) + instruction set are also able to execute binaries compiled for the + i386 (x86) instruction set. This + list is used when fetching files and parsing package lists. The + initial default is always the system's native architecture + (APT::Architecture), and foreign architectures are + added to the default list when they are registered via + dpkg --add-architecture. Default release to install packages from if more than one - version available. Contains release name, codename or release version. Examples: 'stable', 'testing', + version is available. Contains release name, codename or release version. Examples: 'stable', 'testing', 'unstable', '&stable-codename;', '&testing-codename;', '4.0', '5.0*'. See also &apt-preferences;. - Ignore Held packages; This global option causes the problem resolver to + Ignore held packages; this global option causes the problem resolver to ignore held packages in its decision making. @@ -182,106 +195,129 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; - 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 does 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, errors out and - refers to this option so the user can deactivate the immediate configuration temporarily 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 was caused by wrong dependencies of the package - in question or by a system in an already broken state, 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. - Before a big operation like dist-upgrade is run with this option disabled it should be tried to - explicitly install the package APT is unable to configure immediately, but please make sure to - report your problem also to your distribution and to the APT team with the buglink below so they can work on - improving or correcting the upgrade process. + + Defaults to on, which will cause APT to install essential and important + packages as soon as possible in an install/upgrade operation, in order + to limit the effect of a failing &dpkg; call. If this option is + disabled, APT treats an important package in the same way as an extra + package: between the unpacking of the package A and its configuration + there can be many other unpack or configuration calls for other + unrelated packages B, C etc. If these cause the &dpkg; call to fail + (e.g. because package B's maintainer scripts generate an error), this + results in a system state in which package A is unpacked but + unconfigured - so any package depending on A is now no longer + guaranteed to work, as its dependency on A is no longer satisfied. + + The immediate configuration marker is also applied in the potentially + problematic case of circular dependencies, since a dependency with the + immediate flag is equivalent to a Pre-Dependency. In theory this allows + APT to recognise a situation in which it is unable to perform immediate + configuration, abort, and suggest to the user that the option should be + temporarily deactivated in order to allow the operation to proceed. + Note the use of the word "theory" here; in the real world this problem + has rarely been encountered, in non-stable distribution versions, and + was caused by wrong dependencies of the package in question or by a + system in an already broken state; so you should not blindly disable + this option, as the scenario mentioned above is not the only problem it + can help to prevent in the first place. + + Before a big operation like dist-upgrade is run + with this option disabled you should try to explicitly + install the package APT is unable to configure + immediately; but please make sure you also report your problem to your + distribution and to the APT team with the buglink below, so they can + work on improving or correcting the upgrade process. + - Never Enable this option unless you -really- know what you are doing. It - permits APT to temporarily remove an essential package to break a - Conflicts/Conflicts or Conflicts/Pre-Depend loop between two essential - packages. SUCH A LOOP SHOULD NEVER EXIST AND IS A GRAVE BUG. This option - will work if the essential packages are not tar, gzip, libc, dpkg, bash or - anything that those packages depend on. + + Never enable this option unless you really know + what you are doing. It permits APT to temporarily remove an essential + package to break a Conflicts/Conflicts or Conflicts/Pre-Depends loop + between two essential packages. Such a loop should never exist + and is a grave bug. This option will work if the essential + packages are not tar, gzip, + libc, dpkg, dash + or anything that those packages depend on. + - APT uses since version 0.7.26 a resizable memory mapped cache file to store the 'available' - information. Cache-Start acts as a hint to which size the Cache will grow + APT uses since version 0.7.26 a resizable memory mapped cache file to store the available + information. Cache-Start acts as a hint of the size the cache will grow to, and is therefore the amount of memory APT will request at startup. The default value is - 20971520 bytes (~20 MB). Note that this amount of space needs to be available for APT + 20971520 bytes (~20 MB). Note that this amount of space needs to be available for APT; otherwise it will likely fail ungracefully, so for memory restricted devices this value should be lowered while on systems with a lot of configured sources it should be increased. Cache-Grow defines in bytes with the default of 1048576 (~1 MB) how much - the Cache size will be increased in the event the space defined by Cache-Start - is not enough. These value will be applied again and again until either the cache is big + the cache size will be increased in the event the space defined by Cache-Start + is not enough. This value will be applied again and again until either the cache is big enough to store all information or the size of the cache reaches the Cache-Limit. The default of Cache-Limit is 0 which stands for no limit. - If Cache-Grow is set to 0 the automatic grow of the cache is disabled. + If Cache-Grow is set to 0 the automatic growth of the cache is disabled. - Defines which package(s) are considered essential build dependencies. + Defines which packages are considered essential build dependencies. - The Get subsection controls the &apt-get; tool, please see its + The Get subsection controls the &apt-get; tool; please see its documentation for more information about the options here. - The Cache subsection controls the &apt-cache; tool, please see its + The Cache subsection controls the &apt-cache; tool; please see its documentation for more information about the options here. - The CDROM subsection controls the &apt-cdrom; tool, please see its + The CDROM subsection controls the &apt-cdrom; tool; please see its documentation for more information about the options here. The Acquire Group - The Acquire group of options controls the download of packages - and the URI handlers. + The Acquire group of options controls the + download of packages as well as the various "acquire methods" responsible + for the download itself (see also &sources-list;). - Security related option defaulting to true as an - expiring validation for a Release file prevents longtime replay attacks - and can e.g. also help users to identify no longer updated mirrors - - but the feature depends on the correctness of the time on the user system. - Archive maintainers are encouraged to create Release files with the - Valid-Until header, but if they don't or a stricter value - is volitional the following Max-ValidTime option can be used. - + + Security related option defaulting to true, as giving a Release file's + validation an expiration date prevents replay attacks over a long + timescale, and can also for example help users to identify mirrors + that are no longer updated - but the feature depends on the + correctness of the clock on the user system. Archive maintainers are + encouraged to create Release files with the + Valid-Until header, but if they don't or a + stricter value is desired the Max-ValidTime + option below can be used. + - Seconds the Release file should be considered valid after - it was created (indicated by the Date header). + Maximum time (in seconds) after its creation (as indicated + by the Date header) that the Release + file should be considered valid. If the Release file itself includes a Valid-Until header the earlier date of the two is used as the expiration date. - The default value is 0 which stands for "for ever valid". + The default value is 0 which stands for "valid forever". Archive specific settings can be made by appending the label of the archive to the option name. - Minimum of seconds the Release file should be considered - valid after it was created (indicated by the Date header). - Use this if you need to use a seldomly updated (local) mirror of a more - regular updated archive with a Valid-Until header + Minimum time (in seconds) after its creation (as indicated + by the Date header) that the Release + file should be considered valid. + Use this if you need to use a seldom updated (local) mirror of a more + frequently updated archive with a Valid-Until header instead of completely disabling the expiration date checking. Archive specific settings can and should be used by appending the label of the archive to the option name. @@ -290,11 +326,11 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; Try to download deltas called PDiffs for - Packages or Sources files instead of downloading whole ones. True - by default. + indexes (like Packages files) instead of downloading + whole ones. True by default. Two sub-options to limit the use of PDiffs are also available: - With FileLimit can be specified how many PDiff files - are downloaded at most to update a file. SizeLimit + FileLimit can be used to specify a maximum number of + PDiff files should be downloaded to update a file. SizeLimit on the other hand is the maximum percentage of the size of all patches compared to the size of the targeted file. If one of these limits is exceeded the complete file is downloaded instead of the patches. @@ -320,41 +356,41 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; - HTTP URIs; http::Proxy is the default http proxy to use. It is in the - standard form of http://[[user][:pass]@]host[:port]/. Per - host proxies can also be specified by using the form + http::Proxy sets the default proxy to use for HTTP + URIs. It is in the 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. 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 - response under any circumstances, Max-Age is sent only for - index files and tells the cache to refresh its object if it is older than - the given number of seconds. Debian updates its index files daily so the - default is 1 day. No-Store specifies that the cache should never - store this request, it is only set for archive files. This may be useful - to prevent polluting a proxy cache with very large .deb files. Note: - Squid 2.0.2 does not support any of these options. + Three settings are provided for cache control with HTTP/1.1 compliant + proxy caches. + No-Cache tells the proxy not to use its cached + response under any circumstances. + Max-Age sets the allowed maximum age (in seconds) of + an index file in the cache of the proxy. + No-Store specifies that the proxy should not store + the requested archive files in its cache, which can be used to prevent + the proxy from polluting its cache with (big) .deb files. - The option timeout sets the timeout timer used by the method, - this applies to all things including connection timeout and data timeout. + The option timeout sets the timeout timer used by the method; + this value applies to the connection as well as the data timeout. The setting Acquire::http::Pipeline-Depth can be used to - enabled HTTP pipeling (RFC 2616 section 8.1.2.2) which can be beneficial e.g. on - high-latency connections. It specifies how many requests are send in a pipeline. + enable HTTP pipelining (RFC 2616 section 8.1.2.2) which can be beneficial e.g. on + high-latency connections. It specifies how many requests are sent in a pipeline. Previous APT versions had a default of 10 for this setting, but the default value is now 0 (= disabled) to avoid problems with the ever-growing amount of webservers and proxies which choose to not conform to the HTTP/1.1 specification. - Acquire::http::AllowRedirect controls if APT will follow + Acquire::http::AllowRedirect controls whether APT will follow redirects, which is enabled by default. 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.) + which accepts integer values in kilobytes. The default value is 0 which deactivates + the limit and tries to use all available bandwidth (note that this option implicitly + disables downloading from multiple servers at the same time.) Acquire::http::User-Agent can be used to set a different User-Agent for the http download method as some proxies allow access for clients @@ -363,59 +399,65 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; - HTTPS URIs. Cache-control, Timeout, AllowRedirect, Dl-Limit and - proxy options are the same as for http method and will also - default to the options from the http method if they are not - explicitly set for https. Pipeline-Depth option is not - supported yet. + + The Cache-control, Timeout, + AllowRedirect, Dl-Limit and + proxy options work for HTTPS URIs in the same way + as for the http method, and default to the same + values if they are not explicitly set. The + Pipeline-Depth option is not yet supported. + CaInfo suboption specifies place of file that holds info about trusted certificates. - <host>::CaInfo is corresponding per-host option. - Verify-Peer boolean suboption determines whether verify - server's host certificate against trusted certificates or not. - <host>::Verify-Peer is corresponding per-host option. - Verify-Host boolean suboption determines whether verify - server's hostname or not. - <host>::Verify-Host is corresponding per-host option. + <host>::CaInfo is the corresponding per-host option. + Verify-Peer boolean suboption determines whether or not the + server's host certificate should be verified against trusted certificates. + <host>::Verify-Peer is the corresponding per-host option. + Verify-Host boolean suboption determines whether or not the + server's hostname should be verified. + <host>::Verify-Host is the corresponding per-host option. SslCert determines what certificate to use for client - authentication. <host>::SslCert is corresponding per-host option. + authentication. <host>::SslCert is the corresponding per-host option. SslKey determines what private key to use for client - authentication. <host>::SslKey is corresponding per-host option. + authentication. <host>::SslKey is the corresponding per-host option. SslForceVersion overrides default SSL version to use. - Can contain 'TLSv1' or 'SSLv3' string. - <host>::SslForceVersion is corresponding per-host option. + It can contain either of the strings 'TLSv1' or + 'SSLv3'. + <host>::SslForceVersion is the corresponding per-host option. - 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 sets the default proxy to use for FTP URIs. + 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 + will be used. To use an 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 &configureindex; for an example of - how to do this. The substitution variables available are - $(PROXY_USER) $(PROXY_PASS) $(SITE_USER) - $(SITE_PASS) $(SITE) and $(SITE_PORT) - Each is taken from it's respective URI component. + how to do this. The substitution variables representing the corresponding + URI component are $(PROXY_USER), + $(PROXY_PASS), $(SITE_USER), + $(SITE_PASS), $(SITE) and + $(SITE_PORT). - The option timeout sets the timeout timer used by the method, - this applies to all things including connection timeout and data timeout. + The option timeout sets the timeout timer used by the method; + this value applies to the connection as well as the data timeout. Several settings are provided to control passive mode. Generally it is - safe to leave passive mode on, it works in nearly every environment. - However some situations require that passive mode be disabled and port - mode ftp used instead. This can be done globally, for connections that - go through a proxy or for a specific host (See the sample config file + safe to leave passive mode on; it works in nearly every environment. + However, some situations require that passive mode be disabled and port + mode FTP used instead. This can be done globally or for connections that + go through a proxy or for a specific host (see the sample config file for examples). It is possible to proxy FTP over HTTP by setting the ftp_proxy - environment variable to a http url - see the discussion of the http method + environment variable to an HTTP URL - see the discussion of the http method above for syntax. You cannot set this in the configuration file and it is not recommended to use FTP over HTTP due to its low efficiency. @@ -427,45 +469,51 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; - CD-ROM URIs; the only setting for CD-ROM URIs is the mount point, - cdrom::Mount which must be the mount point for the CD-ROM drive - 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 - the cdrom block. It is important to have the trailing slash. Unmount - commands can be specified using UMount. + + For URIs using the cdrom method, the only configurable + option is the mount point, cdrom::Mount, which must be + the mount point for the CD-ROM (or DVD, or whatever) drive 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. + The syntax 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. + - GPGV URIs; the only option for GPGV URIs is the option to pass additional parameters to gpgv. - gpgv::Options Additional options passed to gpgv. + + For GPGV URIs the only configurable option is gpgv::Options, + which passes additional parameters to gpgv. 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 + By 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 + 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 + simply add the preferred type first - default types not already added will be implicitly appended 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"; + configure setting should look like this: Acquire::CompressionTypes::Order { "lzma"; "gz"; }; + It is not needed to add bz2 to the list explicitly as it will be added automatically. + Note that the + Dir::Bin::Methodname + will be checked at run time. If this option has been set, 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 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. + This will not override the defined list; it will only prefix the list with this type. The special type uncompressed can be used to give uncompressed files a preference, but note that most archives don't provide uncompressed files so this is mostly only useable for local mirrors. @@ -482,21 +530,22 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; The Languages subsection controls which Translation files are downloaded - and in which order APT tries to display the Description-Translations. APT will try to display the first - available Description in the Language which is listed at first. Languages can be defined with their - short or long Languagecodes. Note that not all archives provide Translation - files for every Language - especially the long Languagecodes are rare, so please - inform you which ones are available before you set here impossible values. + and in which order APT tries to display the description-translations. APT will try to display the first + available description in the language which is listed first. Languages can be defined with their + short or long language codes. Note that not all archives provide Translation + files for every language - the long language codes are especially rare. The default list includes "environment" and "en". "environment" has a special meaning here: - It will be replaced at runtime with the languagecodes extracted from the LC_MESSAGES environment variable. + it will be replaced at runtime with the language codes extracted from the LC_MESSAGES environment variable. It will also ensure that these codes are not included twice in the list. If LC_MESSAGES is set to "C" only the Translation-en file (if available) will be used. - To force apt to use no Translation file use the setting Acquire::Languages=none. "none" - is another special meaning code which will stop the search for a fitting Translation file. - This can be used by the system administrator to let APT know that it should download also this files without - actually use them if the environment doesn't specify this languages. So the following example configuration will - result in the order "en, de" in an english and in "de, en" in a german localization. Note that "fr" is downloaded, - but not used if APT is not used in a french localization, in such an environment the order would be "fr, de, en". + To force APT to use no Translation file use the setting Acquire::Languages=none. "none" + is another special meaning code which will stop the search for a suitable Translation file. + This tells APT to download these translations too, without actually + using them unless the environment specifies the languages. So the + following example configuration will result in the order "en, de" in an + English locale or "de, en" in a German one. Note that "fr" is + downloaded, but not used unless APT is used in a French locale (where + the order would be "fr, de, en"). Acquire::Languages { "environment"; "de"; "en"; "none"; "fr"; }; Note: To prevent problems resulting from APT being executed in different environments (e.g. by different users or by other programs) all Translation files which are found in @@ -506,24 +555,23 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; - Directories The Dir::State section has directories that pertain to local state information. lists is the directory to place downloaded - package lists in and status is the name of the dpkg status file. + package lists in and status is the name of the &dpkg; status file. preferences is the name of the APT preferences file. - Dir::State contains the default directory to prefix on all sub - items if they do not start with / or ./. + Dir::State contains the default directory to prefix on all + sub-items if they do not start with / or ./. Dir::Cache contains locations pertaining to local cache information, such as the two package caches srcpkgcache and pkgcache as well as the location to place downloaded archives, Dir::Cache::archives. Generation of caches can be turned off - by setting their names to be blank. This will slow down startup but - save disk space. It is probably preferred to turn off the pkgcache rather + by setting their names to the empty string. This will slow down startup but + save disk space. It is probably preferable to turn off the pkgcache rather than the srcpkgcache. Like Dir::State the default directory is contained in Dir::Cache @@ -570,25 +618,30 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; APT in DSelect When APT is used as a &dselect; method several configuration directives - control the default behaviour. These are in the DSelect section. + control the default behavior. These are in the DSelect section. - Cache Clean mode; this value may be one of always, prompt, auto, - pre-auto and never. always and prompt will remove all packages from - the cache after upgrading, prompt (the default) does so conditionally. - auto removes only those packages which are no longer downloadable - (replaced with a new version for instance). pre-auto performs this - action before downloading new packages. + Cache Clean mode; this value may be one of + always, prompt, + auto, pre-auto and + never. + always and prompt will remove + all packages from the cache after upgrading, prompt + (the default) does so conditionally. + auto removes only those packages which are no longer + downloadable (replaced with a new version for instance). + pre-auto performs this action before downloading + new packages. - The contents of this variable is passed to &apt-get; as command line + The contents of this variable are passed to &apt-get; as command line options when it is run for the install phase. - The contents of this variable is passed to &apt-get; as command line + The contents of this variable are passed to &apt-get; as command line options when it is run for the update phase. @@ -599,13 +652,13 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; - How APT calls dpkg + How APT calls &dpkg; Several configuration directives control how APT invokes &dpkg;. These are in the DPkg section. - This is a list of options to pass to dpkg. The options must be specified + This is a list of options to pass to &dpkg;. The options must be specified using the list notation and each list item is passed as a single argument to &dpkg;. @@ -613,16 +666,16 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; This is a list of shell commands to run before/after invoking &dpkg;. Like options this must be specified in list notation. The - commands are invoked in order using /bin/sh, should any + commands are invoked in order using /bin/sh; should any fail APT will abort. - This is a list of shell commands to run before invoking dpkg. Like + This is a list of shell commands to run before invoking &dpkg;. Like options this must be specified in list notation. The commands - are invoked in order using /bin/sh, should any fail APT - will abort. APT will pass to the commands on standard input the - filenames of all .deb files it is going to install, one per line. + are invoked in order using /bin/sh; should any fail APT + will abort. APT will pass the filenames of all .deb files it is going to + install to the commands, one per line on standard input. Version 2 of this protocol dumps more information, including the protocol version, the APT configuration space and the packages, files @@ -632,31 +685,31 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; - APT chdirs to this directory before invoking dpkg, the default is + APT chdirs to this directory before invoking &dpkg;, the default is /. - These options are passed to &dpkg-buildpackage; when compiling packages, + These options are passed to &dpkg-buildpackage; when compiling packages; 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 - multiple 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. + APT can call &dpkg; in such a way as to let it make aggressive use of triggers over + multiple calls of &dpkg;. Without further options &dpkg; will use triggers once each time it runs. + Activating these options can therefore decrease the time needed to perform the + install or upgrade. Note that it is intended to activate these options per default in the + future, but as it drastically changes the way APT calls &dpkg; 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 + production environments. It also breaks progress reporting such that all front-ends 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 + 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 + 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"; @@ -665,53 +718,49 @@ DPkg::TriggersPending "true"; - Add the no triggers flag to all dpkg calls (except the ConfigurePending call). - See &dpkg; if you are interested in what this actually means. In short: dpkg will not run the + Add the no triggers flag to all &dpkg; calls (except the ConfigurePending call). + See &dpkg; if you are interested in what this actually means. In short: &dpkg; will not run the triggers when this flag is present unless it is explicitly 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. + 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 also add this flag to the unpack and remove calls. - 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 - rely 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 implicitly activate also the next option per - default as otherwise the system could end in an unconfigured status which could be unbootable! - + Valid values are "all", + "smart" and "no". + The default value is "all", which causes APT to + configure all packages. The "smart" way is to + configure only packages which need to be configured before another + package can be unpacked (Pre-Depends), and let the rest be configured + by &dpkg; with a call generated by the ConfigurePending option (see + below). On the other hand, "no" will not configure + anything, and totally relies on &dpkg; for configuration (which at the + moment will fail if a Pre-Depends is encountered). Setting this option + to any value other than all will implicitly also + activate the next option by default, as otherwise the system could end + in an unconfigured and potentially unbootable state. - 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 this option is set APT will call dpkg --configure --pending + to let &dpkg; handle all required configurations and triggers. This option is activated automatically + per default if the previous option is not set to all, but deactivating it could be useful if you want to run APT multiple times in a row - e.g. in an installer. In these sceneries you could deactivate this option in all but the last run. - 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 + Useful for the smart configuration as a package which has pending + triggers is not considered as installed, and &dpkg; treats them as unpacked + currently which is a showstopper for Pre-Dependencies (see debbugs #526774). Note that this will process all triggers, not only the triggers needed to configure this package. - - 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. - - - 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). + Essential packages (and their dependencies) should be configured immediately + after unpacking. It is a good idea to do this quite early in the upgrade process as these + configure calls also currently require DPkg::TriggersPending which + will run quite a few triggers (which may not be needed). Essentials get per default a high score + but the immediate flag is relatively low (a package which has a Pre-Depends is rated higher). 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. + example shows the settings with their default values. OrderList::Score { Delete 500; Essential 200; @@ -728,7 +777,7 @@ DPkg::TriggersPending "true"; Periodic and Archives options APT::Periodic and APT::Archives groups of options configure behavior of apt periodic updates, which is - done by /etc/cron.daily/apt script. See header of + done by the /etc/cron.daily/apt script. See the top of this script for the brief documentation of these options. @@ -977,10 +1026,10 @@ DPkg::TriggersPending "true"; - Generate debug messages describing which package is marked + Generate debug messages describing which packages are marked as keep/install/remove while the ProblemResolver does his work. Each addition or deletion may trigger additional actions; - they are shown indented two additional space under the original entry. + they are shown indented two additional spaces under the original entry. The format for each line is MarkKeep, MarkDelete or MarkInstall followed by package-name <a.b.c -> d.e.f | x.y.z> (section) @@ -988,23 +1037,12 @@ DPkg::TriggersPending "true"; d.e.f is the version considered for installation and x.y.z is a newer version, but not considered for installation (because of a low pin score). The later two can be omitted if there is none or if - it is the same version as the installed. + it is the same as the installed version. section is the name of the section the package appears in. - - - - - - Dump the default configuration to standard error on - startup. - - - - -- cgit v1.2.3-70-g09d2