NAME

       apt-config - APT Configuration Query program

SYNOPSIS

       apt-config [--empty] [--format '%f "%v";%n'] [-o=config_string] [-c=config_file] {shell |
                  dump | {-v | --version} | {-h | --help}}

DESCRIPTION

       apt-config is an internal program used by various portions of the APT suite to provide
       consistent configurability. It accesses the main configuration file /etc/apt/apt.conf in a
       manner that is easy to use for scripted applications.

       Unless the -h, or --help option is given, one of the commands below must be present.

       shell
           shell is used to access the configuration information from a shell script. It is given
           pairs of arguments, the first being a shell variable and the second the configuration
           value to query. As output it lists shell assignment commands for each value present.
           In a shell script it should be used as follows:

               OPTS="-f"
               RES=`apt-config shell OPTS MyApp::options`
               eval $RES
           This will set the shell environment variable $OPTS to the value of MyApp::options with
           a default of -f.

           The configuration item may be postfixed with a /[fdbi]. f returns file names, d
           returns directories, b returns true or false and i returns an integer. Each of the
           returns is normalized and verified internally.

       dump
           Just show the contents of the configuration space.

OPTIONS

       All command line options may be set using the configuration file, the descriptions
       indicate the configuration option to set. For boolean options you can override the config
       file by using something like -f-,--no-f, -f=no or several other variations.

       --empty
           Include options which have an empty value. This is the default, so use --no-empty to
           remove them from the output.

       --format '%f "%v";%n'
           Defines the output of each config option. %t will be replaced with its individual
           name, %f with its full hierarchical name and %v with its value. Use uppercase letters
           and special characters in the value will be encoded to ensure that it can e.g. be
           safely used in a quoted-string as defined by RFC822. Additionally %n will be replaced
           by a newline, and %N by a tab. A % can be printed by using %%.

       -h, --help
           Show a short usage summary.

       -v, --version
           Show the program version.

       --audit
           Show audit (and notice) messages. This overrides the quiet option, but only for notice
           messages, not progress ones.

       -c, --config-file
           Configuration File; Specify a configuration file to use. The program will read the
           default configuration file and then this configuration file. If configuration settings
           need to be set before the default configuration files are parsed specify a file with
           the APT_CONFIG environment variable. See apt.conf(5) for syntax information.

       -o, --option
           Set a Configuration Option; This will set an arbitrary configuration option. The
           syntax is -o Foo::Bar=bar.  -o and --option can be used multiple times to set
           different options.

       --no-color, --color
           Turn colors on or off. Colors are on by default on supported terminals for apt(8) and
           can also be disabled using the NO_COLOR or APT_NO_COLOR environment variables, or
           further configured by the APT::Color configuration option and scope, see apt.conf(5)
           for information on that.

SEE ALSO

       apt.conf(5)

DIAGNOSTICS

       apt-config returns zero on normal operation, decimal 100 on error.

BUGS

       APT bug page[1]. If you wish to report a bug in APT, please see
       /usr/share/doc/debian/bug-reporting.txt or the reportbug(1) command.

AUTHORS

       Jason Gunthorpe

       APT team

NOTES

        1. APT bug page
           https://bugs.debian.org/src:apt