Bug#578267: Missing option to skip default configuration

[Goswin von Brederlow <goswin-v-b@web.de>]

Package: apt
Version: 0.7.26~exp3
Severity: normal

Hi,

several sources, projects and user use apt/aptitude as user to
download debian packages and sources. This usualy involves specifying
-c and/or multiple -o options.

The problem now is that even with -c the default configuration file is
always read and there is no way to prevent that. That results in
config options being set that the source, project or user has no
control over. Specifically APT::Update::Pre-Invoke::,
APT::Update::Post-Invoke::, DPkg::Pre-Install-Pkgs:: and so on can
contain entries that are unwanted or even break when run as user and
there is no way to disable them.

There is also the matter of new options beeing added to apt that
existing scripts don't know about and therefore won't
override. Specifically APT::Architectures:: being set in the default
configuration file causes existing scripts to break. And even if the
script knows about it the setting can not be overriden.


So what I am asking for is an option

  --default-config-file <file>
	Configuration File; Specify a configuration file to use. The
        program will read this configuration file instead of the default
        configuration file. See apt.conf(5) for syntax information.

or

  --no-default-config
	Do not read the default configuration file from /etc/apt/.

MfG
	Goswin

-- Package-specific info:

-- (/etc/apt/preferences present, but not submitted) --


-- (/etc/apt/sources.list present, but not submitted) --


-- System Information:
Debian Release: squeeze/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.31.6-xen-2010.02.18 (SMP w/4 CPU cores)
Locale: LANG=C, LC_CTYPE=de_DE (charmap=ISO-8859-1)
Shell: /bin/sh linked to /bin/dash

Versions of packages apt depends on:
ii  debian-archive-keyring        2009.01.31 GnuPG archive keys of the Debian a
ii  libc6                         2.10.2-6   Embedded GNU C Library: Shared lib
ii  libgcc1                       1:4.4.3-7  GCC support library
ii  libstdc++6                    4.4.3-7    The GNU Standard C++ Library v3

apt recommends no packages.

Versions of packages apt suggests:
ii  apt-doc                       0.7.25.1   Documentation for APT
pn  aptitude | synaptic | wajig   <none>     (no description available)
ii  bzip2                         1.0.5-4    high-quality block-sorting file co
ii  dpkg-dev                      1.15.5.6   Debian package development tools
ii  lzma                          4.43-14    Compression method of 7z format in
pn  python-apt                    <none>     (no description available)

-- no debconf information